JPS6052459B2 - Microprogram control method - Google Patents

Description

[Detailed Description of the Invention] The present invention avoids holding microprograms for self-diagnosis errors that do not require holding as a result of retrying the self-diagnosis program, and reports and displays these self-diagnosis errors to other devices. The present invention relates to a microprogram control method.

Conventionally, in a control device such as a magnetic tape control device, a channel device, etc., which performs a predetermined operation based on a command from a control device other than its own device, reports the operation result, and performs a series of processing, The reliability is improved by executing the self-diagnosis program during the idle state, that is, when no operation is being performed.

If an error is detected as a result of this self-diagnosis operation, conventionally execution of the microprogram is stopped and the microprocessor is placed in a hold state. On the other hand, the hardware to be self-diagnosed can be divided into those that are directly related to the execution of microprograms and those that have nothing to do with the execution of microprograms and are only related to command processing operations.

In the former case, normal execution of the microprogram is not guaranteed, so it is necessary to hold the microprogram. In the latter case, the microprogram is held even though it is not necessary to hold it, which is disadvantageous in terms of error cause analysis and error cause display ability of the self-diagnosis program. In addition, if a self-diagnosis error like the latter occurs intermittently, there is room for subsequent command processing to be performed normally, but if it is held, the throughput, that is, the amount of work within a predetermined time, will be reduced. It turns out. An object of the present invention is to provide a microprogram control system that avoids holding self-diagnosis errors that do not require holding the microprogram and reports and displays them to other devices.

To achieve the above object, the microprogram control system of the present invention executes a self-diagnosis program when a predetermined operation is not performed according to a command from another control device, and executes a self-diagnosis program when a self-diagnosis error is detected. A retry will be attempted.

If a self-diagnosis error is detected even in the retry, the microprogram is held and reported to other control devices by other means not controlled by the microprogram. On the other hand, if no self-diagnosis error is detected in the retry, a bit indicating that the retry has occurred is set in the information byte stored as a result of the command operation that is subsequently activated, and the retry is performed. The present invention is characterized in that an error is reported to another control device as a result of the operation. The present invention will be described in detail below with reference to examples.

FIG. 1 is a flowchart showing the operating procedure of an embodiment of the present invention, and is an explanatory diagram of the operation including self-diagnosis of a microprogram control device such as a magnetic tape controller (MTC) as an embodiment.

After the MTC receives a command from another control device, it reports whether or not the operation can be executed by activating the command.

This is the startup status report. If execution is possible, after the activation report process is completed, the MTC moves on to executing the command and performs various operations. After the predetermined operation is completed, the execution result is reported. From starting these commands to reporting the execution results. Self-diagnosis is performed when a series of command operations are not being executed, that is, in an idle state. If an error is detected in the self-bond disconnection, a retry is performed, and if n retries fail, the system is held as in the conventional case. On the other hand, if the retry is successful, it is reported as an error when reporting the execution result of the next activated command, and a sense bit indicating the occurrence of a retry is set in the sense information byte. In this way, when the command execution result is reported as an error, the sense command is activated next to find the cause of the error. The sense command allows other control devices to recognize that a self-diagnosis error has occurred. FIGS. 2A and 2B are detailed explanatory diagrams showing, on a time axis, the above-mentioned operating procedure when the self-diagnosis program of FIG. 1 is executed.

Figure a shows a time when there is no error during self-diagnosis, and after command activation 1, activation status report 2 is performed, and after command execution, execution result report 3 is performed.

Figure b shows a case where the above-mentioned self-diagnosis error occurred and the retry was successful. That is, when a self-diagnosis error occurs, retry flag set 4 is performed, and it is reported as No error 5 in the execution result report 3 of the next command operations 1 to 3.
After the above-described sense command activation 6 and status report 7, a sense bit 8 indicating the occurrence of a retry is set in the sense information byte, and an execution result report 9 is sent to another control device. FIG. 3 is an explanatory diagram of the configuration of an embodiment for realizing the operating procedure explained in FIGS. 2A and 2B. In the figure, a microprocessor 1 reads a microphone instruction code from a microprogram memory 2 according to an address, and performs command processing, self-diagnosis processing, etc.

If an error is detected during self-diagnosis of other hardware 5 in the figure, a retry is performed as shown in FIGS. 2A and 2B. In this case, sense information memory (RAM) 4
The diagnostic retry occurrence bit 41 stored in
The counter 42 retries up to n times. When the retry fails, a hold instruction bit 31 is set in the hold register 3, and a hold signal is sent to the processor 1 and held. In this state, when a command start signal from another control device is input to the microprocessor 1 via the start register 6, the AND circuit 9 generates an interrupt signal using the interrupt status register 10 to which the hold signal was input as the cause of the interrupt. , the hold is reported to other control devices via the 0R circuit 8. On the other hand, if the retry is successful, the interrupt status register 1 will be set to 1 for subsequent command activation.
A status indicating an error is set to 0 by the microprocessor 1, an interrupt register 7 is set, an interrupt signal is generated via the 0R circuit 8, and the activation result is reported. When the other control device reads the contents of the interrupt status register 11 and finds an error, it activates the sense command as shown in FIG. The bytes are received via the data sending circuit 11 and the data bus. Note that commands and data from other control devices are input from a data bus to the microprocessor 1 via a command register 12, a data receiving circuit 13, and a processor read bus. As explained above, according to the present invention, the self-diagnosis program is executed when a predetermined operation is not performed based on a command from another control device, and when a self-diagnosis error is detected, the self-diagnosis is retried. It is done.

For self-diagnosis errors that do not require holding the microprogram as a result of retry, the hold is avoided, and this self-diagnosis error is reported and displayed on other devices.
Other control devices issue sense commands to determine the cause of the error. As a result, the microprogram hold is limited to only those directly related to the execution of the microprogram, which reduces the time in the hold state.Thus, throughput is improved by dealing with intermittent failures, and the ability to display error causes is improved. etc. can be achieved.

[Brief explanation of the drawing]

FIG. 1 is a flowchart showing the operating procedure of the embodiment of the present invention, and FIG.
Figures A and b are detailed explanatory views of the main parts of Figure 1, and Figure 3 is an explanatory diagram of the configuration of an embodiment for realizing the operating procedure of Figure 2. In the figure, 1 is a microprocessor, 2 is a microprogram memory, 3 is a hold register, 31 is a hold instruction bit, 4 is a sense information memory, 41 is a diagnostic retry generation bit, 5 is other hardware, 6 is a start register, 7 is an interrupt register, 8 is 0R Circuit 9 is AND
10 is an interrupt status register, 11 is a data sending circuit, 12 is a command register, and 13 is a data receiving circuit.

Claims (1)

[Claims] 1. In a microprogram control system that performs a predetermined operation based on a command from a control device other than the own device, and when the predetermined operation according to the command is not performed, a diagnostic program for the own device is executed, If an error is detected by the self-diagnosis program, the self-diagnosis program is retried, and when an error is detected in the retry, the execution of the microprogram is stopped and the microprogram control is not relied upon. The termination of the microprogram may be reported by other means, and if no error is detected on a retry, a bit indicating that the retry occurred is included in the information byte stored as a result of a subsequent command operation. , and an error is reported as a result of the operation due to the retry being performed.