JPS6152485B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION In a control system including a processing device, the present invention changes the operating state of the processing device according to the state of a binary signal that is switched depending on the surrounding conditions, thereby changing the function settings of the system. The present invention relates to a device for setting control conditions to be changed.

In recent years, various control systems have been configured using digital control computers called microcomputers (see, for example, Japanese Patent Application No. 1988-88257). There are also cases where it is necessary to change functionality.

In view of this demand, it is an object of the present invention to provide a control condition setting device that allows control conditions to be easily changed.

More specifically, the present invention allows the processing device to be manufactured as an integrated circuit, such as an LSI (Large-Scale Integrated Circuit), by setting a binary signal that determines the control conditions by also using the input/output signal line of the processing device. The purpose is to reduce the number of input/output pins when manufacturing the circuit, reduce the physical size of the circuit body, and reduce the number of assembly steps and parts during manufacturing. According to the present invention, when the processing device is activated, the two
Since the value signal is stored and the own signal processing function is changed using this, the processing function can be easily changed, and after the change, the input/output signal line of the processing device can be used for original signal transmission without any problems. be done.

The present invention will be described below with reference to embodiments shown in the accompanying drawings. In this example, the ignition coil energization start timing and energization cutoff timing (ignition timing) in a four-cylinder gasoline engine among commonly used multi-cylinder engines
The present invention is particularly applied to the ignition control device that controls the ignition control device, particularly to the part that sets the switching between the time control mode and the angle control mode in the numerical data/timing conversion that controls the energization start timing.

In Figure 1 showing the overall configuration of the electrical control system,
Reference numeral 100 denotes a microcomputer used as a digital computer, which performs a calculation process for calculating numerical data that defines the energization start timing and energization cutoff timing of the ignition coil in engine ignition based on various engine control parameters, and the above-mentioned in this ignition control device. Input process of inputting various parameters,
a conversion process for converting the numerical data and time data required for the count value of a predetermined clock signal to reach the numerical data; and a synchronization process for synchronizing the start of conversion in this conversion process with the crank rotation angle of the engine. It has the role of integrally controlling the following based on the control program of the memory 120.
The microcomputer 100 is generally referred to as a processor or CPU, and the microcomputer used in this embodiment is an RCA CDP1802CD.
The accompanying peripheral devices are also commercially available from this series. Hereinafter, it will be simply referred to as a "computer".

Reference numeral 110 denotes an 8-bit bidirectional data bus, through which the computer 100 outputs signals instructing the operation of peripheral devices and binary signals forming the numerical data, and also outputs commands and various data from a memory 120, which will be described later, to a counting circuit. The line from 150 has the role of a line for inputting time data. 130 sends address data specifying a read address of the memory 120 to the memory 120 through an address bus. The memory 120 includes a read-only memory (ROM) that stores control programs that set instructions for various processes in the computer 100 in the order of execution, constants and other data used in calculations, and a read-only memory (ROM) that stores and reads data during calculations. The 8-bit addresses sent from the writable memory (RAM) and the address bus 130 are serialized to 16
It has a built-in address latch that provides a bit address to ROM or RAM. A signal TPA sent from the computer 100 to the memory 120,
TPB, , is the address latch, reading instructions and data from ROM and RAM,
Shows the signals that control writing data to RAM. Note that the functions of the input/output terminals of the computer 100 and their handling are described in the instruction manual published by RCA, so they will not be explained in detail here.

140 is an I/O decoder without a latch function, which can use, for example, CDP1853 manufactured by RCA, and decodes the parallel binary coded signals sent from pins N1, N2, and N3 of the computer 100 and converts them into short pulse-like selections. 141-148 (conductive connections and signals are referred to herein with the same reference numerals) to provide activation signals to peripheral devices of computer 100. The counting circuit 150 is connected to the computer 10
The clock pulse of 4 μs sent from the external clock output terminal CLOCK 0 is divided into 16 bits, counted, and outputted to the timer bus 151 as time data that changes moment by moment. 152 is a switch circuit that receives selection signals 141 and 14 from the I/O decoder.
8 or from the pulse generation circuit 160 described later.
When the DMA progress signal 161 is applied, the time data on the timer bus 151 is sent to the data bus 110. When the selection signal 141 or the DMA progress signal 161 is applied here, the timer bus 151
When the time data of the upper lower 8 bits is sent to the data bus and the selection signal 148 is applied, the upper 8 bits of time data are sent to the data bus.
A bit is sent out. The pulse generation circuit 160
outputs a DMA progress signal 161 and a recognition signal 162 indicating acceptance of interrupt processing as pulses in accordance with signals from output terminals SC1 and SC2 of the computer 100.

A latch circuit 200, an analog multiplexer (MPX) 210, and an analog multiplexer (MPX) 210 are used as input peripheral devices for inputting engine control parameters detected as analog signals to the computer 100.
A digital conversion circuit (A/D conversion circuit) 220 is used. The MPX210 includes various analog signals 210a that serve as a reference for specifying the ignition timing (the timing of cutting off the energization of the ignition coil) and the timing of starting the energization.
~210n (using signals such as intake air amount, engine cooling water temperature, etc. indicating the engine load condition and detection devices thereof are known), and one of them is determined by the output signal of the latch circuit 200. selectively pass one. Latch circuit 20
0 is the selection signal 142 from the I/O decoder 140
computer 100 by latching selected data appearing on data bus 110 in synchronization with
Only the analog signal to be input is MPX21
Specify for 0. 1 passed MPX210
The two analog signals 21 are written in a predetermined location of the RAM of the memory 120 as digital data by the A/D conversion circuit 220.

That is, after one analog signal 211 is selected, the A/D conversion circuit 220
In response to the command 10, the selection signal 143 is received from the I/O decoder 140, and linear integral type A/D conversion is started. Note that immediately before the selection signal 143 is issued, the selection signal 141 is applied to the switch circuit 152, and the time data (lower 8 bits) at the start of A/D conversion is written to a predetermined location in the RAM of the memory 120. . Then, a termination signal 221 generated by the termination of the A/D conversion is sent to the computer 100.
It is input as a DMA request signal and sent to computer 1.
When 00 recognizes this, the DMA progress signal 161
is output and opens the switch circuit 152, and as a result, the time data (lower 8 bits) at the end of A/D conversion is stored in the microcomputer 100.
The data is written directly from the timer bus 151 to the RAM of the memory 120 via the data bus 110 by the DMA function. Therefore, the A/D converted digital data of the analog signal 211 is expressed by calculating the difference between the time data at the start and end of the A/D conversion written in the RAM.

The first-order integral type A/D conversion circuit 220 includes a counter that counts clock pulses of a constant frequency, a circuit that converts the output of this counter into a D/A, and a circuit that converts the output of this counter into a D/A.
Although it may be constructed with a comparator that compares the converted voltage signal with the analog signal 211, the circuit shown in FIG. 2 may also be used.

In FIG. 2, analog input signal 211 is connected via resistor 212 to the non-inverting input terminal of comparator 213, which is provided with hysteresis by resistor 214. A charging circuit is constructed in which a resistor 215 and a capacitor 216 are connected in series with respect to the reference voltage of 5V, and the connection point between the capacitor 216 and the resistor 215 is connected to the inverting input terminal of the comparator 213. An analog switch 217 serving as a switching means is connected in parallel with the capacitor 216, and is opened and closed by a 1-bit A/D conversion command signal output from a terminal of a flip-flop 218, thereby charging and discharging the capacitor 216. 219 sends the A/D conversion stop command signal to flip-flop 2.
This is an OR circuit given to 18. Next, the operation of the A/D conversion circuit having this configuration will be explained using FIG. 3. The relationship between the voltage V _I of the input analog signal 211 and the power supply voltage V _CC (+5V) is V _CC >V _I >0.
This relationship has been established. During initialization, flip-flop 218 is reset, analog switch 217 is closed, and capacitor 216 is discharged. At this time, if the analog input signal 211 of a certain level is applied to the non-inverting input terminal of the comparator 213, the output terminal of the comparator 213 is at the "1" level.

Now, after the computer 100 outputs the selection signal 141 from the I/O decoder according to the control program and writes time data, the computer 100 outputs the selection signal 141 from the I/O decoder and writes the time data, and then at time _t1 , it issues a selection signal 141 to command the start of A/D conversion as shown in FIG. 3b. When one signal 143 is output, the flip-flop 218
is set, and the output of the terminal shown in FIG. 3c goes to the "0" level, opening the analog switch 217. As a result, the terminal voltage of the capacitor 216 shown by the solid line in FIG. 3a increases exponentially. At time _t2 , the voltage _V1 of the input analog signal 211 is introduced into the potential of this inverting input terminal, which becomes higher than the potential of the non-inverting input terminal (horizontal broken line in Figure 3a), and the output terminal goes to the "0" level. Figure 3 d
The DMA request signal 221 shown in
It is input to 0. When computer 100 receives this input, it generates DMA progress signal 161 shown in FIG. 3e to reset flip-flop 218 and close analog switch 217.

Note that since the A/D conversion circuits shown in Figs. 2 and 3 perform nonlinear linear integration, the input analog Digital data having a correct proportional relationship to the signal 211 can be obtained.

Next, initialization of the power supply section of the apparatus and the computer 100 will be explained. 170
is a well-known stabilized power supply circuit, and the on-board battery power supply 1
Converts the normally +12V voltage supplied from the ignition key switch 2 to +5V into a stable voltage. This stable voltage is supplied to all logic blocks not otherwise specified in FIG. 1 and used for their respective operations.

A voltage detection circuit 180 generates a detection signal 181 when the voltage of the battery 1 becomes lower than a predetermined value. 190 is an initialization circuit which provides a command signal for initialization (restarting the control program from the beginning) to the computer 100 in order to prevent the device, particularly the computer 100, from malfunctioning. Initialization is performed either when the detection signal 181 representing the battery voltage is at a low level or when an abnormal operation of the computer 100 is detected in the DC regeneration circuit 191.

FIG. 4 shows details of the voltage detection circuit 180, which consists of a time constant circuit shown in frame a and a comparison circuit shown in frame b. FIG. 5 is an operation time chart of the voltage detection circuit shown in FIG. 4. A voltage signal 2a is applied to the time constant circuit a when the key switch 2 is closed, and when the voltage signal 2a rises (for example, as shown in FIG.
When the voltage signal 2a falls (for example, at the time _t3 in Fig. ₅ ), the diode 1 rises with a time constant determined by the capacitor 182 and the resistor 183.
The charge stored in the capacitor 182 is discharged through the capacitor 84, resulting in a voltage signal 185 that falls sharply. This voltage signal 185 is divided by a resistor (not shown) in the time constant circuit a, and this divided voltage 186 is applied to the reference voltage 18 in the comparator circuit b.
7 (e.g. 4V). Comparison circuit b performs this comparison using a switching circuit consisting of two transistors coupled with positive feedback, and when the divided voltage 186 exceeds the reference voltage 187 at time t ₂ due to the rise of the voltage signal 2a, the switching output 188 is output. becomes almost the same potential as the voltage signal 2a, and during loads such as rotation of the starter motor for starting the engine, the divided voltage 1 becomes as shown in t ₃ - _{t 4} .
When 86 falls below reference voltage 187, switching output 188 is at a potential equal to ground. The role of the time constant circuit a is to provide an initialization signal with a sufficient time width to the computer 100 when impulse noise is added to the voltage signal 2a. The resistor 189 is for converting the switching output 188 at the battery voltage level to a logic level (about 5V).

The initialization circuit 190 includes a Schmitt NAND circuit 193 that sets the output signal 194 to the "1" level when either the detection signal 181 of the voltage detection circuit 180 or the reproduction output signal 192 of the DC reproduction circuit 191 becomes below a threshold level. , an inverter 195 that inverts the logic level and applies an initialization signal of "0" level to the computer 100, and a resistor 196 that feeds back the output signal 194 of the Schmidt Nand circuit 193 to the DC regeneration circuit 191, an example of which is shown in FIG. A DC regeneration circuit 191 shown in FIG.

In FIG. 6, in order to simplify the explanation, the capacitors 191a and 191b are assumed to have the same capacitance C ₀ , and the "1" level of the repeated pulse signal 422 supplied to the DC regeneration circuit 191 is
Vh volts (usually +5V), and the period of this "1" level is sufficiently longer than the charging time constant of the capacitor. Also, the explanation will be given first while ignoring the feedback resistor 196. Initially, the charges charged in capacitor 191a and capacitor 191b are zero. Assume that the signal 422 reaches the "1" level for the first time at time t1, as shown in FIG. _7a . At this time, the charging current flows from the capacitor 191a to the diode 191d.
to ground through capacitor 191b. Further, since the diode 191c has a direction opposite to this charging current, no current flows to the ground through this diode. Find the charge Q ₁ that flows through this capacitor DC charging circuit and accumulates in each capacitor. Assuming that the forward resistance of the diode 251 is R, a solution of Q ₁ =CoV/2 is obtained from the transient equation expressed as Rdq/dt+1q/Co+1q/Co=V. Therefore, the potential of the signal 192 becomes 1/2 of the potential of the signal 422, that is, Vh/2.

Next, when the signal 422 becomes "0" level at time t ₂ , Q ₁ =
The CoVh/2 charge is short-circuited through the diode 191c and disappears. However, the charge accumulated in the capacitor 191b is prevented from flowing out by the diode 191d. As a result, terminal 191e
The potential of signal 192 is zero volts, and the potential of signal 192 is Vh/2 volts. This completes the first cycle.

Next, when the signal 422 becomes "1" level for the second time, a charge is similarly passed through the capacitor series charging circuit.
Q ₂ is about to flow. However, the difference from the first time is that a charge of Q ₁ =CoVh/2 already exists in the capacitor 191b. Therefore, it is now necessary to find the charge Q ₂ flowing through this circuit from the transient equation expressed as Rdq/dt +1/Coq+1/Co (q+Q ₁ )=V. Therefore, Q ₂ = CoVh - Q ₁ /2 = CoVh
/2- CoVh/4 is obtained. In other words, the capacitor 191a accumulates a charge of CoVh/2-CoVh/4,
A charge of CoVh/2+CoVh/4 is accumulated in the capacitor 191b. As a result, signal 192 will be (V/2+V/4) volts. Subsequently, the above process is repeated by repeatedly inverting the level of the pulse signal 422, and the signal 192 becomes (V/2+V/4+V/8+...) and finally reaches V volts.

However, in reality, a feedback resistor 196 is connected between the output terminal of the DC regeneration circuit 191 and the output terminal of the Schmitt-Nand circuit 193, and depending on the level of the output signal 194 of the Schmitt-Nand circuit 193, the feedback resistor 196 is connected for charging. , used for discharge. For the sake of explanation, the Schmidt NAND circuit 193 is represented as a switch 193a as shown in FIG. Battery voltage drops abnormally and detection signal 181 becomes “0”
level, then Schmitt Nand circuit 1
The output signal 194 of 93 becomes "1" level (the computer 100 is initialized), and the capacitor 191b is charged via the feedback resistor 196.

When the battery voltage is at a normal level sufficient to obtain a stabilized voltage of +5V and the detection signal 181 is at the "1" level, the charge in the capacitor 191b is gradually discharged via the feedback resistor 196.
Therefore, if the repeated pulse signal 422 is no longer applied to the DC regeneration circuit 191, the capacitor 19
The charge on 1b will eventually be discharged. By configuring the repetitive pulse signal 422 to be generated by the normal progress of the control program of the computer 100, the repetitive pulse signal 422 disappears (maintains at "0" level) due to runaway of the control program, and the capacitor When the charge on 191b, that is, the voltage level of signal 192, becomes lower than the threshold level of Schmitt NAND circuit 193, signal 194 becomes "1" level for initialization.

When the signal 194 becomes "1" level, the capacitor 191b is charged by the resistor 196,
When the voltage level of the signal 192 becomes equal to or higher than the threshold level of the Schmitt NAND circuit 193, the signal 194 becomes the "0" level and the initialization is completed.
By initialization, the computer 100 returns the control program to its initial state and restarts it. This operation is shown after time _t3 in the time chart of FIG.

FIG. 8 illustrates the operation of initialization circuit 190 when key switch 2 is closed but repeat pulse signal 422 is not applied to DC regeneration circuit 191 due to a failure in computer 100 or related circuitry. When the key switch 2 is closed at time _t1 in FIG. 8, a stabilized voltage of +5 V shown in FIG. 8a is applied from the stabilized power supply circuit 170 to the logic block of the device. If the battery voltage 2a is higher than the predetermined reference voltage, the voltage detection circuit 180 sets the detection signal 181 to the "1" level (of course higher than the threshold level of the Schmidt Nand circuit 193) at time _t2 , _slightly later than time t1. do. At time _t2 , the reproduction output of the DC reproduction circuit 191 is at the "0" level, and therefore the output 194 of the Schmidt NAND circuit 193 is at the "1" level between t1 _{and t3} in FIG. 8d. Therefore, the capacitor 191b of the DC regeneration circuit 191 is charged via the feedback resistor 196 even though the repeated pulse signal 422 is not applied. DC regeneration circuit 191 by charging
The reproduction output (voltage) 192 gradually rises, and when it reaches the threshold level of the Schmitt NAND circuit 193 shown in FIG. 8C at time _t3 , the output 194 of the Schmitt NAND circuit 193 becomes "0"
Flip to level. Therefore, the capacitor 191b is
At time t ₄ , Schmitt Nand circuit 1 shown in Figure 3d
The voltage is gradually discharged until the threshold level of 93 is reached. In this way, the capacitor 191b of the DC regeneration circuit 191 receives the repeated pulse signal 42.
Unless t 2 occurs, the feedback resistor 196 and the Schmitt-Nand circuit 193 perform an oscillating action, and t ₁
The initialization signal for the computer 100 is repeatedly generated between t3 and _t3 , between _t4 and _t5 , between _t6 and _t7, and so on.

In the initialization circuit 190, the time constant for charging and discharging the capacitor 191b of the DC regeneration circuit 191 is kept constant by one feedback resistor 196, but the time constant for charging and discharging the capacitor 191b of the DC regeneration circuit 191 is kept constant using two resistors. A time constant may be determined. For example, a resistor with a small resistance value is connected in series with a diode that allows only charging current to flow from the output terminal of the Schmidt Nand circuit 193 toward the capacitor 191b, and connected to the position of the resistor 196, and then connected in parallel with this series circuit with a resistor with a large resistance value. The resistor may be connected in series with a diode that allows only the discharge current to flow from the capacitor 191b toward the output terminal of the Schmitt-Nand circuit 193. This will cause the ignition key switch 2 to
When the detection signal 181 of the voltage detection circuit 180 rises after turning on the capacitor 191b, the capacitor 191b is immediately turned on.
can be charged, and the computer 100 can be quickly put into operation.

Next, a description will be given of peripheral devices for inputting the engine rotation speed as one of the control parameters for ignition calculation in the computer 100 and synchronizing the numerical data of the calculation result to convert it into ignition control timing. 300 is a known angle detector for detecting the crank rotation angle, that is, the rotation angle of the engine, and a gear mechanically connected to rotate in synchronization with the engine crankshaft;
It is comprised of a waveform shaping circuit that shapes the output signal of an electromagnetic pickup, which is fixed relative to the rotating gear, into rectangular wave pulses.
The angle detector 300 has two sets of detectors each consisting of a rotating gear, an electromagnetic pickup, and a waveform shaping circuit. One generates a reference pulse 301 at a reference position of the engine rotation angle, for example, near top dead center, and the other One is to generate an angle pulse 302 at every predetermined interval of the engine rotation angle. Angle detector 3
Since the structure and electric circuit of 00 are well known, detailed explanation will be omitted. Of course, other types of angle detectors that do not use electromagnetic pickups can also be used.

The advantage of this device is that the angle interval of the engine rotation angle that outputs the angle pulse as this angle detector is
For angle counting type of 1° or 2°, or
Whether it is a 30° or 60° time counting type, it is an integration of hardware that allows the timing of the energy conversion process in the engine to precisely match the planned engine rotation angle. However, it is necessary to externally indicate to this control device whether an angle detector of the angle counting type or the time counting type is connected. Of course, it would also be possible to attach an electrical device that determines how many angle pulses 302 occur during one cycle of the reference pulse 301 sent from the angle detector 300 and automatically issues an instruction. However, it is uneconomical and not very desirable to provide such a device. Also, the control program is different between the angle counting type (mode) and the time counting type (mode), but this is based on the angle detector 30.
When changing the type of 0, only the ROM in the memory 120 containing the control program needs to be replaced. Although it would be possible to implement a configuration in which this ROM is automatically switched by the above-mentioned electrical device, it is uneconomical to incorporate two control programs into the device and to attach a switching device, so it is not desirable. do not have. Therefore, in this embodiment, the control program is replaced with the ROM depending on whether the control device is configured as an angle counting type (angle counting mode) or a time counting type (time counting mode). .

Reference numeral 310 denotes a mode switching circuit for specifying whether the mode is angle counting mode or time counting mode based on the surrounding conditions. A latch circuit 320 latches the mode signal 311 specified by the mode switching circuit 310 at the timing of initializing the computer 100, and holds the mode signal after the initialization of the computer 100 is completed. 330 is an angle signal processing circuit which converts the reference pulse 301 and angle pulse 302 from the angle detector 300 into mode signals 321 and 322 held in the latch circuit 320.
The information is processed and inputted to the computer 100 according to the following.

FIG. 9 shows an example of the configuration of the mode switching circuit 310 and the latch circuit 320. 320a is an integrated circuit forming a single latch circuit, which in this embodiment is a CD4042BE made by RCA. Latch circuit 32
0a is a non-inverting output terminal when the signal 194 is at "1" level indicating initialization of the computer 100.
At _Q1 , an output signal 322 having the same level as the signal 311 at the input terminal _D1 is generated, and at the inverted output terminal ₁ , an output signal 322 at an inverted level is generated. Further, when the initialization is canceled and the signal 194 goes to the "0" level, the output signal 321 is at the same level as the input signal 311 immediately before going to the "0" level, and the inverted level.
322 results. The mode switching circuit 310 is connected to terminal 3.
13 and resistors 312 and 314 selectively connected to the +5V power line or ground line. In this example, the resistor 312 or 314 is selectively connected as a switch element, and when the resistor 312 shown by the solid line is connected, a "1" level signal is applied to the input terminal _D1 , and the resistor 3 shown by the broken line is connected.
When 14 is connected, a "0" level signal is applied. Here, when the input signal 311 is at "0" level (with the resistor 314 connected), the angle counting mode is activated.
The terminal 313, which sets the time counting mode when the input signal 311 is at the "1" level (with the resistor 312 connected), indicates the connection between the computer 100 and its peripheral devices, such as the latch circuit 320 and the angle signal processing circuit 330. It forms a pin when the peripheral devices it contains are integrated into a single _LSI (Large Scale Integrated Circuit) circuit element. Therefore, according to this configuration, LS _I
There is no need to add pins to the converted circuit elements for mode switching. This pin terminal 313 is connected to the resistor 31
Since the resistor 2 or resistor 314 is provided, signals at normal logic levels can be exchanged between the computer 100 and peripheral devices after initialization (latched state). In this embodiment, the angle signal processing circuit 3
The output signal 333 of 30 can be input to the flag input terminal EF4 of the computer 100 via the terminal 313. However, the present invention is not limited to this, and it is also possible to connect a resistor to another signal line and use that signal line for transmitting the control input of the latch circuit. Although not shown, the terminal 313 is used for mode switching and for the computer.
It is also possible to implement it by providing each of them independently without using them for connecting peripheral devices.

Details of the angle signal processing circuit 330 are shown in FIG. The angle signal processing circuit 330 consists of a part used for both the angle counting mode and the time counting mode, a part used exclusively for each mode, and a part selected by the mode switching signal. A reference pulse 301 and an angle pulse 302 inputted from the angle detector 300 are converted into a reference signal 341 at a logic level (+5V) and an angle signal 34 by a Schmitt NAND circuit 36 and an inverter 337, and a Schmitt NAND circuit 338 and an inverter 339, respectively.
It is converted to 2,343 and input. When the engine control device operates in the angle counting mode, the frequency division circuit 340 outputs an interrupt frequency division pulse 344 at every predetermined engine rotation angle (crank rotation angle).

The frequency dividing circuit 340 constitutes an interrupt processing circuit when in the angle counting mode, and includes a NAND circuit 345 for input control of the angle signal 342, a decade counter 346,
347, inverters 348 and 349, NAND circuits 350 and 351 forming flip-flops, and a NOR circuit 352. The operation of this frequency dividing circuit 340 will be explained with reference to the timing chart of FIG. In this embodiment, the reference pulse 301 (reference signal 341) and the angle pulse 30 (angle signal 342) in the angle counting mode are spaced at 2° intervals and
It is set at 360° intervals. Furthermore, the pulse value of the "1" level of the reference signal 341 is assumed to be 60 degrees, and the top dead center of the cylinder is located at a position near the trailing edge (for example, a position rotated 8 degrees from the trailing edge), and the "1" level pulse value of the angle signal 342 is The pulse width of the 1” level is 1°,
It is also assumed that the angle detector is adjusted so that the rise of the reference signal 341 and the rise of the angle signal are synchronized.

Now, when the reference signal 341 reaches the “1” level,
The counters 346 and 347 are reset, and the carry-out signal CO353 of the counter 346 is set to "1" level and the counter 347 is set to the "1" level as shown in FIG.
The sixth output signal 354 shown in FIG. 11 and the ninth output signal 355 shown in FIG. 11e are at the "0" level. When the ninth output signal 355 becomes "0" level, the inverted signal 356 by the inverter 349 becomes "1" level, and therefore the NAND circuit 345 shown in FIG.
The output signal 357 is input to the counter 346 as a logical inversion output of the angle signal 342. However, since the counter 346 is in a reset state during 60 degrees due to the reference signal 341, no counting operation is performed. When the engine rotates 60 degrees and the reference signal 341 reaches the "0" level, the counters 346 and 347 enter the counting state, and the counter 346 converts the angle signal 342 into 10
The counter 347 outputs one carry-out signal 353 each time it counts, that is, one carry-out signal 353 for every 20 degrees of engine rotation angle, and the counter 347 reaches the "1" level when it counts the sixth carry-out signal. A sixth output signal 354 (FIG. 11d) is generated, and a ninth output signal 355 (FIG. 11e) which rises to the "1" level when counting the ninth one is generated. Therefore, the sixth output signal 354 and the ninth output signal 35
The flip-flop 35 is activated by the logic inversion signal of 5.
0,351 is set and reset, Figure 11C
After rotating 180 degrees from the rising edge of the reference signal 341 shown in FIG. 11, a pulse signal 357 having a width of 60 degrees shown in FIG. Further, when the rotation is 180 degrees, the logically inverted signal 356 of the ninth output signal 355 goes to the "0" level, so the NAND circuit 345 fixes the output signal 357 to the "1" level as shown in FIG. 11B. Therefore, from this point on, counting is suspended until the reference signal 347 rises again. The NOR circuit 352 outputs the first signal according to the NOR of the reference signal 341 and the flip-flop output signal 357.
Interrupt frequency division pulses 344 that go to the "0" level at 180° intervals as shown in FIG. 1g are generated.

Reference numeral 358 denotes a counting clock generation circuit, which is used only when the engine control device operates in the angle counting mode and uses the angle pulse 302 (angle signals 342, 343) as a counting clock signal. The counting clock generating circuit 358 receives the angle signal 3.
42 and 343 are synchronized with the operating clock 101 of the computer 100 (in this embodiment, the period is 4 μs), so that one clock signal 334 is generated for every 1 degree of engine rotation angle, and one clock signal 335 is generated for every 2 degrees of engine rotation angle. arise.

The counting clock generation circuit 358 is composed of D-type flip-flops 359, 360, 361 and an exclusive OR circuit 362, and when the clock input (terminal CL) rises, the level of the input signal (terminal D) is maintained. FIG. 12 shows changes in signal levels at each part. Flip-flop 359 transfers angle signal 342 to computer 100.
A synchronized clock signal 33 whose level is inverted every 2° at the rising edge of the operating clock signal 101.
Convert to 5. As shown in FIG. 112, a flip-flop 360 transmits the asynchronous angle signal 343 shown in FIG. 12a to the computer 10 shown in FIG. 12b.
It is converted into synchronized clock signals 363 and 364 shown in FIGS. 112c and 112d, in which the level is inverted at the rising edge of the 0 operating clock signal. Furthermore, one synchronization clock signal 363 is transferred to the flip-flop 3.
61 results in a resynchronized clock signal 365 delayed by one clock as shown in FIG. 12e. By extracting the mismatch between the synchronized clock signal 364 and the resynchronized clock signal 365 using the exclusive OR circuit 362, a synchronized clock signal 335 of every 1° as shown in FIG. 12f is obtained. The operation of flip-flops 259 and 360 is practically equivalent;
Synchronization clock signal 3 of flip-flop 360
64 may be outputted from the terminal 335 as a clock signal every 2 degrees.

366 is an interrupt processing circuit in the time counting mode, and the reference pulse 301 (reference signal 341)
D-type flip-flop 36 that latches
7. Flip-flop 36, also of type D, which latches the angle pulse 302 (angle signal 342).
8, and a NOR circuit 369, the reference signal 3
When either the angle signal 41 or the angle signal 342 reaches the "1" level, the NOR circuit 369 generates an interrupt pulse 370 of the "0" level. When the engine control device is in the time counting mode, the interrupt pulse 37
When 0 is recognized by the computer 100, the pulse generation circuit 160 outputs an interrupt recognition signal 162, and the flip-flops 167 and 168 are reset. As a result, in time counting mode, the reference position of the engine rotation angle and the predetermined (30° or 60°
100 is interrupted at intervals of 100°. In the time counting mode in this embodiment, the start timing of numerical data/timing conversion is created at intervals of every 30° or 60° of the engine rotation angle, but the timing of the interrupt, the start of energization at ignition, and the interruption of energization. Regarding the relationship with (ignition) timing,
This will be clarified in the time chart of the overall operation, which will be explained later along with the angle mode.

A selection circuit 371 includes a selection circuit 372 that switches the interrupt pulses 344 and 370 between the angle counting mode and the time counting mode, and a multiplexer 373 that switches between the reference signal 341, the angle signal 342, and the frequency division signal 357. The selection circuit 372
The AND/OR selection circuit of RCA CD4019BE can be used, and the mode signals 321,
322 is input from the latch circuit 320, the angle counting mode interrupt pulse 370 is sent to the interrupt terminal of the computer 100 as the interrupt request signal 331.
Input to INT. Also, AND/OR selection circuit 3
When the mode signals 321 and 322 are input to the control input terminal a of 72 at the "0" level and the control input terminal "b" to the "1" level, meaning the angle counting mode, the interrupt signal for the time counting mode is input. The frequency pulse 344 is input to the computer 100 as an interrupt request signal 331.

The multiplexer 373 uses RCA's CD4053BE, and when a "0" level signal is applied to the inhibit input terminal, the signals at the input terminals ax and ay, and bx and by are selected according to the level of the mode signal 321. and occurs at output terminals a and b. When the mode signal 321 is at the "1" level, that is, in the time counting mode, the input terminals ay and by are connected to the output terminals a and b, respectively, and therefore the angle signal 342
and reference signal 341 are output as flag input signals 332 and 333 of computer 100. In the time counting mode, when the computer 100 receives the interrupt request signal 331, the signal 332, which is input to the flag input terminals 1 and 2,
By checking the level of 333, it is possible to recognize whether the engine rotation angle is at the reference position or at what angular position from the reference position. When the mode signal 321 is at "0" level, that is, in the angle counting mode, the input terminal of the multiplexer 373
ax and bx are coupled to the output terminals a and b, respectively, so that the reference signal 341 and the flip-flop 3
50 and 351 (a signal delayed by 180 degrees with respect to the reference signal 341) 357 are input to the computer 100 as flag input signals 332 and 333. Computer 1 in angle counting mode
00 means that the engine rotation angle is at the reference position or 180 degrees from the reference position based on the signal level of the flag input terminal when the interrupt request signal 331 is input.
It is possible to recognize whether the camera is in the ゜ position. The inverters 374 and 375 are for inputting the "1" level initialization signal 194 to the multiplexer 373 as a logic level inhibit signal.
When the initialization signal 194 is at the "1" level, the output terminals a and b are at an open level (FLOAT), so that the signal line 333 can be used for coupling the mode switching circuit 310 and the latch circuit 320. Signals 331, 332, 333 input from the angle signal processing circuit 330 to the computer 100
is also used to input the engine rotational speed, which will be described in detail later.

In FIG. 1, 380 is a clock signal switching circuit which switches a clock signal 381 in numerical data/time data conversion, which will be described later, according to the level of a mode signal 321. Clock signal switching circuit 38
0 is a synchronized clock signal 335 every 2 degrees from the angle signal processing circuit 330 or a clock signal 153 with a constant cycle every 128 μs from the counting circuit 150.
respectively, the level of the mode signal 321 is “0”,
Select by “1”. This clock signal switching circuit 380 utilizes the same switching conditions as the multiplexer 373 in the angle signal processing circuit 330, and may be combined with the multiplexer 373. The 128 .mu.s clock signal 153 can be taken out as the 5th bit count output obtained by dividing the 4 .mu.s clock signal from the computer 100 in the 16-bit counting circuit 150.

Here, it is one of the control parameters used to calculate the timing of cutting off the energization of the ignition coil (and also the timing of starting energization) when igniting the engine.
The process of inputting the engine rotation speed will be explained. As mentioned above, the computer 100 performs interrupt processing in response to the interrupt request signal 331 from the angle signal processing circuit 330, and outputs the flag input signals 332, 3.
It is determined whether the engine rotation angle is at the start position of numerical data/timing conversion based on the signal level of 33, and if it is at the start position, the conversion is started. Further, when a predetermined engine rotation angle, for example, a reference position, is reached, the switch circuit 152 is connected to the I/O
Alternative signals 141, 14 via O decoder 140
8 is applied, and the time data at that point is stored in the memory 12.
Write to the specified location in RAM 0. Therefore, in the subsequent calculation process, the time per revolution of the engine can be determined by determining the time difference between the previous time data and the time data from the time before the previous time. This time difference is the reciprocal of the engine rotation speed. Note that due to the time difference in the generation of the alternative signals 141 and 148, a difference occurs in the time data when the lower 8 bits of time data are input and when the upper 8 bits are input, but the generation interval of the alternative signals 141 and 148 is controlled. Since it is fixed by the program, it is normalized in the calculation process for calculating the time difference.

Next, numerical data/timing conversion will be explained. In FIG. 1, reference numerals 400 and 410 are converter circuits constructed of hardware, which convert numerical data specifying the ignition energization start timing or energization cutoff timing given from the digital computer 100 to a clock signal from the clock signal switching circuit 380. A signal 381 or a clock signal 334 from the angle signal processing circuit 330 is used to count down, and at the end of the down-count, a signal specifying each timing of the ignition is generated. Similar conversion circuits of this type are also disclosed in JP-A No. 50-90826 ``Engine Control Method and Apparatus'' and JP-A 53-8434 ``Ignition Timing Control Method for Internal Combustion Engine.'' .

The conversion circuit 400 is also used to determine when to start energization in both the angle counting mode and the time counting mode, and the presettable down counter 4
01 and a NAND circuit 402. The presettable down counter 401 is manufactured by RCA, for example.
When a command signal 144 is applied from the computer 100 via the I/O decoder 140, binary value data that specifies the timing to start energization on the data bus 110 is synchronized with this. At the same time as the presetting, the zero detection signal (ZERO DETECT) 403 is set to the "1" level (provided that the binary value data is greater than zero). Yotsute Nando circuit 4
02 becomes "open" to the clock signal 381 and provides the counter 401 with a clock signal 404 for down counting. When the initial preset value in the counter 401 disappears due to down counting (counting), the zero detection signal 403
becomes the "0" level, causing the NAND circuit 402 to be "closed" and ending counting. Zero detection signal 4
03 is given to the ignition amplifier circuit 3 via a NAND circuit 405 as a logic circuit, and the zero detection signal 40
The timing of starting energization is defined by the timing of reversal from the "1" level to the "0" level in No. 3. As mentioned above, by switching between the angle counting mode and the time counting mode, the clock signal 381 for counting is changed to the clock signal 335 indicating the engine rotation angle every 2 degrees and 128μ.
s is selected, the conversion circuit 400 can perform both numerical data/timing conversion in the angle counting mode and conversion in the time counting mode without applying an external command signal. can do.

The conversion circuit 410 is used to determine when to cut off the current in the angle counting mode, and the conversion circuit 410
Presettable down counter 411 similar to 0
and a NAND circuit 421. Then, when the selection signal 145 is applied from the computer 100 via the I/O decoder 140, the counter 41
1 presets the binary value data that defines the power cutoff timing on the data bus 110 in synchronization with this, and at the same time sets the zero detection signal 413 to the "1" level. Therefore, the NAND circuit 412 receives the clock signal 33.
The counter 41 becomes “open” for 4.
A clock signal 414 for down-counting is applied to the clock signal 414. When the first preset value in the counter 411 disappears due to down-counting, the zero detection signal 413 goes to the "0" level, causing the NAND circuit 412 to be in the "closed" state and ending counting.
The zero detection signal 413 is connected to one of the flag input terminals EF2 of the computer 100. When the computer 100 causes the conversion circuit 410 to start conversion using the selection signal 145 at a predetermined engine rotation angle, the computer 100 monitors the level of the zero detection signal 413 and detects the zero detection signal once at the "1" level. When 413 is inverted to the "0" level, it is recognized that it is the current cutoff timing, that is, the ignition timing.

In this embodiment, when the angle conversion circuit 410 completes counting, the computer 100
The control program is set to command the start of counting. When the angle signal processing circuit 330 applies the interrupt request signal 331 to the computer 100 at a predetermined engine rotation angle, the computer 1
00 outputs numerical data defining the power-off timing to the data bus 110, and at the same time outputs the selection signal 145 from the I/O decoder 140, causing the conversion circuit 410 to start conversion. During this conversion operation, the computer 100 outputs a zero detection signal 413.
is monitored, and a zero detection signal 413 is generated upon completion of conversion.
When it reaches the "0" level, numerical data specifying the start time of energization is outputted to the data bus 110, and at the same time, the selection signal 144 is outputted from the I/O decoder 140 to cause the conversion circuit 400 to start conversion. While the zero detection signal 403 is at the "1" level indicating that this conversion is in progress, the output signal 406 of the NOR circuit 405 is at the "0" level, and when this output signal 406 reaches the "0" level, the ignition starts. The energization to the primary coil 4a of the coil 4 is cut off, a high voltage for ignition is induced in the secondary coil 4b, and when the output signal 406 reaches the "1" level due to the completion of conversion, energization to the primary coil 4a is started. Ru.

Reference numeral 420 denotes a latch circuit, which has the function of generating a signal 421 for controlling the NOR circuit 405 as a logic circuit by cooperating with the conversion circuit 400 to generate a signal indicating the energization start time and the energization cutoff time, and for the progress of the control program. It has a function of repeatedly giving a pulse signal 422 to the DC regeneration circuit 191 in accordance with the request.
The latch circuit 420 synchronizes with the selection signal 146 of the I/O decoder 140 and receives a signal from the computer 100 via a predetermined bit of the data bus 110.
By latching the value signal, the above control signal 4
21 and a repeated pulse signal 422 are obtained. As mentioned above, when the ignition control device shown in this embodiment is operated in the angle counting mode, the result is 1
Since the timing of the energization start time and the energization cutoff time can be obtained from the output signals of the two conversion circuits 400, the control signal 421 of the latch circuit 420 is always fixed at the "0" level, and the output signal 406 of the NOR circuit 405 is Zero detection signal 4 of counter 401
03.

On the other hand, in the energization counting mode, in this embodiment, the timing of the energization start time is set by the conversion circuit 400.
This occurs due to the software conversion in the computer 100, and the latch circuit 420 and NOR circuit 405 integrate both timings to shut off the power at the "0" level and turn off the current at the "1" level. An ignition control signal 406 for energizing is obtained.

A known ignition system is used. The ignition amplifier circuit 3 receives the output signal 406 of the NOR circuit 405.
is amplified and the semiconductor switching element 3a is turned on and off by the amplified signal 3b. As a result, the primary coil 4a of the ignition coil 4 is energized and cut off.
When the current is cut off, a high voltage for ignition is generated in the secondary coil 4b. A high voltage for ignition is supplied to the spark plugs of each cylinder through a known distributor (not shown) which is rotated synchronously by the engine, and ignites the cylinders.

In this ignition control device, the energization time of the primary coil 4a is set such that the current value immediately before the interruption of the primary coil 4a is ensured so that the high voltage for ignition induced in the secondary coil 4b has a sufficient energy level. and determines when to start energizing. For this purpose, a current detection circuit 470 and a time data latch circuit 480 are provided to measure the time from when the primary coil 4a starts energizing and reaches a reference current value until the energization is cut off. The memory 120 is used as a control parameter to calculate the start time.
Store in RAM. The current detection circuit 470 includes a resistor 471 having a minute resistance inserted into the current-carrying path of the primary coil 4a, and a resistor 471 that is
The voltage comparator 473 compares the voltage generated at the resistor 471 with the voltage generated by the reference voltage 472. When the voltage drop across the resistor 471 reaches the reference voltage due to an increase in the primary current, the voltage comparator 473 outputs a detection signal 474.
(“1” level) occurs.

The latch circuit 480 is manufactured by RCA, for example.
A CDP1852CD (I/O port) can be used and is used exclusively as an input port in this embodiment. The latch circuit 480 then outputs the detection signal 474.
The time data on the timer bus 151 is latched at the timing of occurrence (from "0" level to "1" level), and at the same time, a service request signal ( ) 481 indicating the latched state is sent to the computer 100.
occurs as a flag input. computer 10
When the write signal ( ) 102 from 0 to the memory 120 (RAM) and the selection signal 147 via the I/O decoder 140 are applied (both at the "1" level), the latched data is transferred to the data bus. 110 and memory 120
Write to (RAM). On the other hand, at the moment when the primary coil 4a is de-energized (with a slight time difference in the program), the computer 100 switches the switch circuit 1.
52 through the I/O decoder 140.
41 is applied, and the time data at that point is written from the timer bus 151 to the memory 120 (RAM). Then, through software processing, the time data obtained from the latch circuit 480 is subtracted from the time data obtained via the switch circuit 152, thereby measuring the duration of the current flowing in the ignition primary coil 4a at or above the reference current value. can do.

In FIG. 13, the computer 100 is connected to the memory 120.
Among the processes performed according to the control program of the (ROM), the process related to calculating the timing to start energization is shown. This energization start timing control is roughly divided into programs that satisfy the following four conditions.

(1) Feed back the measured value of the duration of the reference current as negative feedback to determine the next energization time.

(2) Set the calculated value of the energization time to the expected value of the reference current duration (determined in advance based on the heating characteristics of the ignition coil, the volume characteristics of the ignition energy, and the margin for compensating for transient conditions). to be followed.

(3) Correct the calculated value of the energization time according to the deviation between the measured value of the reference current duration and the previous measured value.

(4) When the engine is rotating at high speed, etc., the timing of starting energization should be adjusted to ensure the minimum cut-off time required for the release of ignition energy by cutting off the energization.

The computer 100 calculates the timing to start energization (calculates the energization time), and the ignition coil 4
The basic closing time B (the time from the start of energization to the reference current, which may be corrected by software depending on the ambient temperature, etc.) determined in advance through experiments etc., and the reference current. The expected value 0 of the duration, the duration T of the reference current in the previous energization of the target energization (time) to be calculated, and the stored value M of the calculation result F of the reference current made two times before that. Add using the polarity shown. The calculated value A, which constitutes the energization time as a result of the addition, is calculated as the crank rotation angle at which energization starts in the case of angle counting mode, or as the predetermined crank rotation angle in the case of time counting mode, with respect to the calculated value P of the ignition timing. It is converted and corrected into numerical data D representing the actual time from the time to the start of energization. Further, at this time, in order to correct the above (4), the numerical data D may be corrected to be smaller based on the calculated value P of the ignition timing (previous value).

The finally obtained numerical data D is input from the computer 100 to the aforementioned numerical data/period data (timing) conversion circuit 400, and the command signal 1
44, the conversion is started and the timing for starting energization of the ignition coil 4 in ignition control is defined. When the current in the primary coil 4a exceeds the reference current due to energization, the detection signal 474 of the current detection signal 470 goes to the "1" level, and the time data at that point is transferred to the latch circuit 48.
0 and at the same time the service request signal 4
81 is at the "0" level indicating that the reference current has been reached.
When the zero detection signal 413 of the numerical data/period data conversion circuit 410 is generated (angle counting mode in this embodiment), or when counting is completed by software processing of the computer 100, the computer 10
0 issues a command to cut off the current through the signal 144 or 421, and further, the computer 100 checks the flag input 3 and issues a service request signal 48.
1 is at the "0" level indicating that the reference current has been reached (YES) or not (NO). When YES, the latch circuit 4 is
By subtracting the latched time data from 80, the duration T of the reference current or more is determined. Further, if the flag input 3 remains at the "1" level, it is determined that the duration T of the reference current is absent.

The first addition X in FIG. 13 corrects the expected value O of the duration of the reference current by the deviation between the measured duration T of the reference current and the stored value M at the previous addition force. and the second addition y is the first
This means adding the calculated value F based on the addition force and the basic closing time B.

The microcomputer 10 is mainly shown in Figure 1 above.
0 and the input/output peripheral circuits operatively connected to it, focusing on the characteristic parts of their individual roles.Next, we will discuss the operation as an ignition control device in angle counting mode and time counting mode. This will be explained with reference to a flowchart and a timing chart of the control program.

14 and 15 show the control program and the timing of control output in the angle counting mode. Control programs can be broadly divided into
It is assembled from an initialization routine A, a main calculation routine B, and an interrupt processing routine C.

The initialization routine A is executed by the initialization signal 194 from the initialization circuit 190, and repeatedly pulses the DC regeneration circuit 191 when the ignition key switch 2 is turned on or when the computer 100 malfunctions. When 422 is no longer applied, the control program once changes all the registers and peripheral devices in the computer to their initial states and restarts the process. Also, when the initialization signal disappears, the latch circuit 3
20 latches the operating mode of ignition control.

At the end of the initialization routine, computer 1
The state where interrupts to 00 are prohibited is released and the process moves to main calculation routine B. In the main calculation routine B, various engine control parameters are input and the ignition timing (angle) and energization start angle are calculated. When each calculation is completed, the ignition timing and energization are started again after a process of outputting a repeated pulse. Repeat the angle calculation. All of these calculation methods, except for the example shown in FIG. 13, can be adopted as known methods, so they will not be described in detail here. Among the engine control parameters necessary for calculation, analog input signals 210a to 210n are processed by a latch circuit 200,
MPX210, A/D conversion circuit 220 and DMA
By using the function, the engine rotation speed is controlled by controlling the switch circuit 152 based on the angle signal from the angle signal processing circuit 330.
Furthermore, the duration of the reference current when energizing the ignition coil 4 can be determined by using the switch circuit 152 and the latch circuit 480 in the memory 120.
(RAM) can be written to a predetermined address.
Calculations are performed in accordance with a predetermined calculation method by successively reading out necessary control parameters from the memory 120 (RAM).

If you want to calculate the ignition timing and energization start angle immediately after initialization, the input process for the engine speed, which is one of the control parameters, is done based on the interrupt processing routine related to ignition operation, so it is difficult to calculate the ignition timing and energization start angle. It may occur that the ignition operation is not completed in time for the actually required ignition operation. Therefore, in the initialization routine A, if the ignition timing is fixed (e.g. BTDC8°) and the energization start angle (e.g.
BTDC68°) is set once, and if the calculation cannot be done in time, ignition operation can be performed using this fixed numerical data. Main calculation routine B is fast (number
ms), the repeated pulse 42
The inversion of the signal level in step 2 is performed using the main calculation routine B.
It is programmed to be performed once every several to several tens of repetitions, and is matched with the charging/discharging time constant of the DC regeneration circuit 191 and resistor 196.

The interrupt processing routine C is executed by the angle signal processing circuit 330.
When the interrupt request signal 331 from
The processing is temporarily interrupted, and under the control of the computer 100, processing for commanding numerical data/period data conversion in the conversion circuits 400 and 410 and processing for inputting the rotational speed of the engine are performed.

In FIG. 15, a is the angle signal processing circuit 330.
10, which is the same as signal 344 in FIG. 10 in angle counting mode. By adjusting the angle detector 300, the interrupt request signal 331 changes from the engine rotation angle of BTCC68°.
The level is “0” up to BTDC8°, and between BTDC248° and BTDC188°. The ignition timing (ignition angle) required for the engine to be controlled is from 68 degrees to 8 degrees before the dead center of the compression process.
When the interrupt request signal a is inverted from the "1" level to the "0" level at BTDC68° or BTDC248°, the computer 100 starts the main calculation routine B.
Immediately after completing one instruction processing cycle being executed in , the interrupt processing routine C is entered, and the main processing routine B is saved. Next, data bus 1
10, numerical data indicating the ignition timing (engine rotation angle at which power is cut off, expressed in 2° increments from BTDC 68°) is sent as a command signal 14.
5 causes the counter 411 of the conversion circuit 410 to be preset. The counter 411 immediately starts counting down in response to the angle clock signal 334 every 2 degrees of engine rotation angle, and during counting, the counter 411 is shown in FIG.
As shown in the figure, the zero detection signal 413 is set to "1" level, and is inverted to "0" level at the timing of the end of counting. The period data _T1 obtained by this count corresponds to preset numerical data, and is executed by the main calculation routine B of the computer 100.
Specify the ignition timing calculated by

After presetting the numerical data, the computer 100 sends a command signal 141 to the switch circuit 152 to write time data into the memory 120 (RAM), and then continues to monitor the zero detection signal 413 input to the flag input terminal 3 to detect zero. Detection signal 413
When it becomes "0", it is determined that it is the ignition timing (YES), and numerical data indicating the energization start timing is sent to the counter 401 of the conversion circuit 400 via the data bus 110 (1 degree from the energization cutoff angle to the energization start angle). (expressed in units of angle) is preset by command signal 144. As a result, the counter 40
1 immediately starts counting down with the angle clock signal 335 every 1 degree, and during counting, the clock signal 335 shown in FIG.
As shown in , the zero detection signal 403 is set to "1" level, and is inverted to "0" level at the timing of the end of counting. Output signal 421 of latch circuit 420
Since the ignition control signal 406 remains at the "0" level and does not change (the "0" level may be set at any time by the computer 100), the ignition control signal 406 is equal to the zero detection signal 4.
The level is determined depending on 03. counter 401
The period data _T2 obtained by counting corresponds to the preset numerical data, and defines the energization start timing necessary to obtain the desired ignition energy (current energization duration). The ignition control signal 406 is amplified by the ignition amplifier circuit 3 and becomes an amplified signal 3b shown in FIG. 7e.
is applied to the switching element 3a to cause the ignition to take place. Note that t ₁ and t ₃ indicate ignition timing, t ₁ - _{t 2} indicates energization is cut off, and t ₂ - _{t 3} indicates energization.

When the computer 100 commands de-energization by the command signal 144, it immediately sends the command signal 141 to the switch circuit 152 in order to calculate the duration of the reference current in the energization (main calculation routine B).
is given and the time data is written into the memory 120 (RAM). After completing this, the computer 100
Wait until BTDC8° or BTDC188°.
When BTDC8° or BTDC188° is reached, a command signal 141 is given from the computer 100 to the switch circuit 152, and the time data is stored in the memory 120.
(RAM). Therefore, to find the engine rotation speed in main processing routine B,
From BTDC68° to BTDC8° or BTDC248
All you have to do is find the newer time difference from ° to BTDC188 ° by subtraction.

When BTDC8° or BTDC188° has passed and input of time data is completed, the computer 100 returns the temporarily interrupted main calculation routine B to the interrupted position and repeats the main calculation routine B until an interrupt occurs. In addition, from BTDC68° to BTDC8°, the output signal 3 of the angle signal processing circuit 330
32 is “1” level, BTDC248° to BTDC188
Since the output signal 333 is at the "1" level until this point, the computer 100 can distinguish between the flag input terminals 1 and 4 by checking the flag input terminals 1 and 4. Therefore, it is also possible to obtain the engine rotational speed only once in one rotation of the engine.

Next, the operation of the ignition control device in the time counting mode will be described. Here, we will explain the time counting mode using an angle detector that obtains angle pulses at one reference position of the engine rotation angle and at angular intervals of 30 degrees.
Angular intervals of 30° are not an absolute requirement for control, and 45° or 60° intervals can be accommodated by simply changing the software. Furthermore, since it is sufficient to specify the engine rotation angle necessary for control in relation to the reference position, the interval between the angular positions does not have to be constant everywhere.

FIG. 16 shows the operating state of the angle signal processing circuit 330 and the computer 10 in the time counting mode.
This shows the timing of ignition control based on 0. The angle signal processing circuit 330 is the angle detector 300
produces an output signal 333 shown in FIG. 16b in synchronization with the reference pulse 301 from the angle pulse 30.
2, an output signal 332 shown in FIG. 16a is generated and applied to the flag input terminals 4 and 1 of the computer 100, respectively. As shown,
The output signal 332 indicating the angle is the engine rotation angle.
The ignition timing range to be controlled by this device is approximately BTDC68° to BTDC8, with intervals of 30°.
Range up to 98°, previous angular position BTDC98°
Output signal 33 indicating the reference position between BTDC68°
3 arrives at the "1" level. Output signal 3
32 and 333 as well as their pulse widths are limited by the mechanical configuration of the angle detector 300. In this embodiment, the pulse width is set to approximately 10 degrees of the engine rotation angle.

Interrupt request signal 331 shown in FIG. 16c
(“0” level) is generated by the interrupt processing circuit 366 (see FIG. 10) every time the reference pulse 301 and the angle pulse 302 are generated. computer 1
When 00 accepts interrupt processing, interrupt recognition signal 16
2, the interrupt request signal 331 is “1”.
Get to the level and wait.

The first control program in time counting mode
It is shown in Figure 7. The initialization routine A and the main calculation routine B are roughly the same as in the angle counting mode. The only difference is that the numerical data obtained as a result of the ignition timing calculation and the energization start timing calculation is a value that is once calculated as the rotation angle of the engine and then converted into a value representing time. Of the numerical data representing this time, the numerical data representing the ignition timing corresponds to the time starting from BTDC68°, and the numerical data representing the energization start time is
It corresponds to the time starting from any one of BTDC 338°, 308°, or 278°. When representing the start time of energization, it is simultaneously specified based on the calculation result whether the starting point is 338°, 308°, or 278° BTDC.

In the interrupt processing routine C, the position of the engine rotation angle after the main routine evacuation is determined based on the signal levels of the flag input terminals EF1 and EF4, and processing is selected based on this. When the reference position interrupt occurs at BTDC83°, the computer 10
0 temporarily sets the internal count value of the angular position interrupt to zero, and then when interrupts are applied to BTDC68°, 38°, 8°, etc., the first interrupt, 2nd interrupt, etc.
The interrupt positions are sequentially identified and determined, such as the second interrupt, the third interrupt, and so on.

When an interrupt occurs at BTDC 68° (or 248°), the computer 100 stores memory 120.
(RAM), 16-bit and 24-bit numerical data is set by using the specified address N (multiple addresses), and the set numerical data is repeatedly down-counted by the command cycle of 16 μs period by the computer 100. Every time the down count of "1" is completed, it is determined whether the numerical data has reached zero or not, and the process is repeated until the numerical data reaches zero.
Time T ₁ in FIG. 16e shows the counting process by the computer 100. The timing at which the count result becomes zero is the actual ignition timing as a result of the ignition timing calculation.
When the count result becomes zero, the computer 100
controls data bus 110 and command signal 146 to output signal 4 of latch circuit 420 shown in FIG. 16f.
21 is inverted to "1" level. At this time, the conversion circuit 400 has already completed the conversion.
The BTDC 403 is at the "0" level, so the ignition control signal 406 (see FIG. 16h) is inverted to the "0" level at the timing when the output signal 421 is inverted to the "1" level.

An interrupt request of 38° BTDC may occur in the process of numerical data/timing conversion by the computer 100 itself. In this case, the conversion will be temporarily interrupted, but this problem can be avoided by using software processing to delay the ignition command depending on whether the BTDC38° interrupt occurs or not. For example, the numerical data that specifies de-energization is calculated in advance as a smaller value by the amount that will delay the ignition command, and if an interrupt occurs during the conversion of the numerical data/timing, the ignition command is delayed and the If you don't have one, you can create a program that doesn't cause delays. In addition, in the angle detector 300, BTDC38
A structure may be adopted in which the angle pulse 302 of .degree. is not generated.

After ignition (cut off current), BTDC8°, 338°,
When an interrupt occurs at 308°, 278°, etc., the computer 100 determines that the interrupt angle is the starting point for converting numerical data/period data for starting energization, based on the result of the energization start timing calculation in main calculation routine B. (YES) or not (NNO) (whether or not energization start control is performed). Now, we have obtained the calculation result that the energization start time is t ₃ with respect to the energization cutoff timing t ₄ , and the starting point is determined to be BTDC308°,
Suppose that the time point after T ₂ from BTDC308° is defined by numerical data when converted to time. When the computer 100 is interrupted at 308° BTDC, it sets the conversion circuit 400 according to the timing of the command signal 144 via the numerical data bus 110 that defines the period T ₂ . The counter 401 immediately
A down count is started by the 128 μs clock signal 153, and the zero detection signal 403 is inverted to the "1" level as shown in FIG. 16g. Computer 100 then uses the data bus to send command signal 14.
5, the output signal 421 of the latch circuit 420 is inverted to the "0" level, and the ignition control signal 406, which is the output signal of the NOR circuit 405, becomes the zero detection signal 403.
make it dependent on In other words, the output signal 421
When the voltage is inverted to “0” level, the conversion circuit 400
When the zero detection signal 403 inverts to the "0" level at the timing of the end of the conversion, the ignition control signal 406
is inverted to "1" level. The engine in this embodiment has four cylinders, and ignition is performed approximately every 180 degrees of engine rotation angle, so the angle pulse is 3.
A control program may be prepared so as to start energization and cut off energization at a predetermined interrupt position corresponding to 02.

In the amplified signal 3b of the ignition control signal 406,
At the time of reversal to “1” level t ₁ and t ₃ , energization starts,
The time points t ₂ and t ₄ of reversal to the “0” level indicate the interruption of energization.

In the interrupt based on the angle pulse 302, if the engine rotation angle is not suitable for controlling the start or cut off of energization, the process returns to main calculation routine B and repeats the process.

Note that in this embodiment, in the time counting mode, the numerical data/period data regarding power cutoff is converted using the time counting function of the computer 100's own software. It may also be modified to do so. For example, the configuration of the conversion circuit 410 used only in the angle counting mode may be changed to the configuration of the conversion circuit 400.
It is also possible to adopt a dual-purpose configuration as shown in FIG. 3, and select the counting pulse or the clock signal of a predetermined frequency in the angle counting mode in the same way as the clock signal switching circuit 380.

By equipping the input/output signal line of the processing device with a resistor that generates a binary signal through a switching operation and a memory circuit that stores this binary signal in synchronization with startup, processing functions can be easily changed. , the input/output signal line can be used for original signal transmission and can achieve the intended purpose.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the overall configuration of an embodiment in which the present invention is applied to an ignition control device, FIG. 2 is an electrical wiring diagram showing details of the A/D conversion circuit 220 in FIG. 1, and FIG. is a time chart for explaining the operation of the A/D conversion circuit in FIG. 2, FIG. 4 is an electrical wiring diagram showing details of the voltage detection circuit 180 in FIG. 1, and FIG. 5 is the voltage detection circuit in FIG. 4. FIG. 6 is an electrical wiring diagram showing details of the DC regeneration circuit 191 in FIG. 1, and FIG.
FIG. 8 is a time chart for explaining the operation principle of the DC regeneration circuit shown in FIG. 6, and FIG. 8 is a time chart for explaining the operation of the DC regeneration circuit shown in FIG.
FIG. 9 is an electrical wiring diagram showing details of the mode switching circuit 310 and latch circuit 320 in FIG.
The diagrams are electrical wiring diagrams showing details of the angle signal processing circuit 330 in FIG. FIG. 10 is a time chart for explaining the operation of the counting clock generation circuit 358 in the angle signal processing circuit, and FIG. 13 is a time chart showing the energization start timing in ignition control among the processes performed by the computer 100 in FIG. 1 according to the control program. FIG. 14 is a flowchart showing the flow of the control program when the computer 100 controls the angle counting mode, and FIG. 15 is the angle counting process of the ignition control device in FIG. 1. FIG. 16 is a time chart diagram for explaining the operation of the ignition control device in the time counting mode. FIG. 17 is a time chart diagram for explaining the operation of the ignition control device in the time counting mode. It is a flowchart diagram showing a flow. 100... Digital computer, 190... Initialization circuit, 194... Initialization timing signal line, 31
0...Mode switching circuit as a switching circuit, 312,
314...Resistor, 320...Latch circuit as a memory circuit, 321, 322...Control input signal line, 330
...Angle signal processing circuit as a signal processing circuit, 33
3 (311)...Signal line.

Claims (1)

[Claims] 1. A first means constituted as an integrated circuit body that selects and performs a predetermined process, and a second means that receives an output signal of the first means from its output terminal and performs a predetermined operation. and a third means for generating a binary signal at the output terminal via a resistor by a switching operation of the connecting means, the first means comprising a connecting means operated according to the surrounding conditions, and a binary signal is generated at the output terminal via a resistance. , synchronously at startup, the third
A control condition setting device comprising a storage means for inputting and storing a binary signal from the means through the output terminal, and performing the predetermined processing according to the stored value.