JP5542491B2 - Digital recorder - Google Patents

Description

  The present invention relates to a digital recorder having a firmware update function as a control program.

  Until now, many digital recorders for monitoring mainly for detecting and monitoring suspicious persons have been proposed. In recent years, many of these digital recorders are equipped with a functional graphical user interface (hereinafter simply referred to as “GUI”), an advanced network communication function, and the like, and there is a trend toward higher functionality.

  Under such circumstances, the frequency of updating firmware, which is a control program for controlling the main operation of the digital recorder, tends to increase.

  On the other hand, digital recorders are often operated continuously for 24 hours when used for monitoring purposes, etc. However, when updating firmware, the digital recorder should be operated (recorded) for about 5 to 10 minutes. It is necessary to stop the operation, and it is necessary to prepare another recorder for alternative operation in order to guarantee the 24-hour continuous operation even during the stop period.

  Thus, in a digital recorder that requires continuous operation for 24 hours, if the firmware of the digital recorder can be updated without stopping the system (operation) of the digital recorder even during video recording, It becomes very convenient because the alternative operation of the recorder is unnecessary.

  In a digital recorder that is recording video or the like, a microcomputer (CPU (Central Processing Unit), hereinafter simply referred to as “CPU”) as a control unit executes a control operation based on firmware. For this reason, it is virtually impossible to rewrite the firmware itself used by the CPU during the control operation without adversely affecting the control operation content of the CPU. Therefore, there is currently no digital recorder that can update firmware during recording.

  Further, the multi-CPU system as disclosed in Patent Document 1 realizes that the process of downloading software for each CPU is executed with almost no influence on the normal service being operated by another CPU. . In this way, one solution can be considered in which firmware update during recording is realized by applying a method of adding a CPU and a program having almost the same functions to a digital recorder.

JP-A-10-260845

  However, when a system (CPU and program) having the same function is newly added as in Patent Document 1, since the circuit scale for the addition becomes large, it occupies a lot of space such as a board, and is developed. Since the scale also increases, there is a problem that it is disadvantageous in terms of cost in total.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to obtain a digital recorder capable of firmware update processing with a relatively simple configuration even during recording of external information such as video.

According to a first aspect of the present invention, there is provided a digital recorder for recording data based on external information obtained from the outside, and compressing the digital signal based on the external information to obtain compressed data A data compression unit, a data transfer unit that performs data transfer processing for transferring the compressed data and recording the data on a predetermined recording device, the compression processing by the data compression unit, and the data transfer processing by the data transfer unit. An auxiliary control unit for controlling, a control program storage unit for storing a control program for controlling the main operation of the digital recorder, and a main control unit for executing a main control operation based on the control program. Can update the contents of the control program in the control program storage unit. A shared information holding unit accessible from the auxiliary control unit and the main control unit, wherein the shared information holding unit stores a control parameter for controlling the compression processing by the data compression unit. The control parameter includes first and second control parameters, and the control information storage unit includes first and second control information storage units for storing the first and second control parameters. The auxiliary control unit includes the first control stored in the first control information storage unit by the main control unit during control of at least the data recording operation of the main control operation of the main control unit. read the parameter, based on the control parameters of the first controls the compression processing by the data compression unit, the running of the update process of the control program by the main control unit Oite, said main control unit reads the second control parameter stored in the storage unit for the second control information, and controls the compression processing by the data compression unit on the basis of the control parameters of the second Yes.

Stored in the digital recorder according to claim 1, wherein in the present invention, the auxiliary control unit, during the execution of the update processing by that control program major controller, the main control unit to the second control information storage unit It reads the second control parameter, and controls the compression processing by the data compression unit on the basis of the control parameters of the second. Therefore, even during the control program update process, the compressed data based on the external information can be recorded on the recording device without any trouble under the control of the auxiliary control unit.

  As a result, there is an effect that the continuous recording of the compressed data can be performed without any trouble while updating the control program without preparing another equivalent digital recorder and performing the alternative operation.

  In addition, the auxiliary control unit and the control information storage unit need only have a function of performing the minimum necessary control for realizing a recording function to a predetermined recording device, so that the digital control can be performed with a relatively simple circuit configuration. A recorder can be configured.

It is a block diagram which shows the system configuration | structure of the digital recorder which is Embodiment 1 of this invention. It is explanatory drawing which shows typically the operation | movement content of CPU and the recording microcomputer part at the time of normal operation mode setting. It is explanatory drawing which shows typically the operation | movement content of CPU and the recording microcomputer part at the time of firmware update mode setting. 4 is a flowchart illustrating a processing procedure of firmware update processing in the digital recorder according to the first embodiment. 10 is a flowchart illustrating a processing procedure of firmware update processing in the digital recorder of the second embodiment. It is a block diagram which shows the structure of the conventional digital recorder used as the premise technique of this invention. It is a flowchart which shows the process sequence of the firmware update in the conventional digital recorder.

<Prerequisite technology>
FIG. 6 is a block diagram showing a general configuration of a conventional digital recorder, which is a prerequisite technology of the present invention.

  As shown in the figure, the camera 20 outputs a video / audio analog signal S20 acquired from a predetermined internal imaging device to the digital recorder DR9.

  The conventional digital recorder DR9 includes an A / D conversion unit 11, a video processing unit 12, a CODEC 13, a recording device 14, a data transfer unit 15, a CPU 16, a RAM 17, a flash memory 18, and a USB port 19.

  The A / D converter 11 converts the input video / audio analog signal S20 into a video / audio digital signal S11.

  The video processing unit 12 outputs to the CODEC 13 an image processed digital signal S12 obtained by processing the input video / audio digital signal S11 by image processing such as enlargement or reduction.

  The CODEC 13 is data compression means for obtaining compressed data D13 by using a compression technique such as JPEG or MPEG for the uncompressed image processed digital signal S12 input from the video processing unit 12.

  The data transfer unit 15 realizes mutual data transfer using the buses of the CODEC 13 and the recording device 14, respectively.

  Next, the role of the CPU 16 will be described. The CPU 16 controls the entire digital recorder DR9 and manages various information. Specifically, there are a wide variety of functions such as data transfer control for recording / reproduction and data transfer, control of various interfaces such as CODEC 13 and GUI, recording data management, and clock management function. These functions are realized by the CPU 16 executing a control program implemented as firmware. However, in the state where only video recording is performed, the processing load of the CPU 16 is not so high because the role of the CPU 16 is mainly limited to the control of the CODEC 13 and the like.

  Note that the GUI is for enabling a user to perform various settings on the screen by operating the personal computer (PC) GUI. The interface control is, for example, for controlling a USB or LCD. In the recording data management, when the data received from the CODEC 13 is stored in the recording device 14 such as an HDD, the order of the data is changed or the contents of the data are slightly changed so that the data can be easily reproduced later. Means. The clock management function is a function for embedding the current time in the data received from the CODEC 13 so that the time can also be displayed during reproduction.

  Next, the firmware update mechanism will be described. The firmware update is realized by the CPU 16 transferring the firmware to be updated stored in the USB memory (not shown) via the USB port 19 and storing it in the flash memory 18.

  During the update of the firmware, the CPU 16 cannot execute the control operation based on the firmware. Therefore, it is necessary to stop all the functions of the digital recorder DR9, and of course, the recording function for video and the like must also be stopped.

  FIG. 7 is a flowchart showing a firmware update processing procedure in the conventional digital recorder DR9. Hereinafter, the firmware update processing content in the conventional digital recorder DR9 will be described with reference to FIG.

  First, in step ST21, recording is first stopped (REC STOP) from step REC (REC STOP) in step ST22 from the REC state (video recording state), and then in step ST23, the power is turned off (POWER OFF).

  In step ST24, the firmware is updated in a state where the CPU 16 has stopped recording video and the like. Thereafter, the power is turned on (POWER ON) in step ST25, and then the REC state is restored in step ST26.

  As described above, in the system configuration of the conventional digital recorder DR9, it is impossible in principle to perform the firmware update process while continuing to record video and the like.

<Embodiment 1>
FIG. 1 is a block diagram showing a system configuration of a digital recorder according to Embodiment 1 of the present invention.

  In the embodiments shown in this specification (Embodiment 1 and Embodiment 2), digital data obtained by content processing from external information such as video / audio signals from a camera or the like is used by a data compression means. A typical digital recorder having a function of compressing and storing the compressed data in a recording device such as an HDD is assumed.

  As shown in FIG. 1, a digital recorder DR1 that receives a video / audio analog signal S20 that is external information from a camera 20 includes an A / D conversion unit 1, a video processing unit 2, a CODEC 3, a recording device 4, a data transfer unit 5, The signal processing control unit 6, RAM 7, CPU 8, flash memory 9, and USB port 10 are included.

  As shown in FIG. 1, the camera 20 outputs a video / audio analog signal S20 acquired from a predetermined internal imaging device to the digital recorder DR1.

  The A / D converter 1 converts the input video / audio analog signal S20 into a video / audio digital signal S1.

  The video processing unit 2 outputs to the CODEC 3 an image-processed digital signal S2 obtained by processing the input video / audio digital signal S1 by image processing such as enlargement or reduction.

  The CODEC 3 is a data compression unit that performs compression processing on the uncompressed image processed digital signal S2 input from the video processing unit 2 using a compression technique such as JPEG or MPEG, and obtains compressed data D3. . The compression processing by the CODEC 3 is executed based on the control signal SC obtained from the signal processing control unit 6.

  The data transfer unit 5 realizes mutual data transfer processing using the buses of the CODEC 3 and the recording device 4 (predetermined recording device), respectively, transfers the compressed data D3 to the recording device 4, and The data transfer process such as recording the compressed data D3 is performed. The data transfer process by the data transfer unit 5 is executed based on a control signal S6 obtained from the signal processing control unit 6.

  The signal processing control unit 6 includes a recording microcomputer unit 6a, a control register group 6b, a control register group 6c, and a firmware update state notification register group 6d.

  The recording microcomputer unit 6a gives the control signal S6 and the control signal SC to the signal processing control unit 6 and the CODEC 3, and controls the operations of the data transfer unit 5 and the CODEC 3. That is, the recording microcomputer unit 6a functions as a first microcomputer (auxiliary control unit).

  The register groups 6b to 6d, which are shared information holding units, function as shared information holding means that can be read and written from the recording microcomputer unit 6a and a CPU 8 to be described later.

  As described above, the CPU 8 that is the second microcomputer (main control unit) can read and write to the register groups 6 b to 6 d and can also read from and write to the RAM 7 and the flash memory 9. The flash memory 9 which is a control program storage section stores a control program for control operation by the CPU 8 called firmware, and can be rewritten by the firmware CPU 8.

  The signal processing control unit 6 is roughly classified as described above, from the recording microcomputer unit 6a that functions as the first microcomputer that controls the data transfer unit 5 and the signal processing control unit 6, the recording microcomputer unit 6a, and the CPU 8. The read / write register groups 6b to 6d are classified.

  Register groups 6b to 6d are control register groups 6b and 6c for storing control parameters for CODEC control, and a firmware update state notification register group 6d that can be written to and read from internal and external devices for firmware update state notification. It consists of.

  Control register groups 6b and 6c, which are control information storage units, include control data including setting data such as a frame rate value and image quality parameter value set for the CODEC 3, and parameters such as recording start, stop, and image request. Is stored.

  The firmware update status notification register group 6d, which is a control program update status notification storage unit, stores information that allows the CPU 8 to notify the signal processing control unit 6 of the firmware update status (update start, update stop). Have been prepared for.

  Based on the values stored in the register groups 6b to 6d, the recording microcomputer unit 6a gives the control signal SC including the control parameter to the CODEC 3, and controls the compression processing by the CODEC 3.

  Further, the recording microcomputer unit 6a gives the control signal S6 to the data transfer unit 5 to control the data transfer unit 5, and the compressed data D3 input from the CODEC 3 is recorded into a recording device represented by a memory, HDD, or the like. 4 also has a data transfer control function to be transferred to. The data transfer control function, the recording data management function, the clock management function, etc. by the recording microcomputer unit 6a are realized by executing a dedicated program stored in an internal memory (not shown) or the like.

  The recording microcomputer unit 6a uses a microcomputer having a simple configuration that is less expensive than the CPU 8, and realizes the above-described control parameter setting, data transfer control function, and the like. This is because the functions required of the recording microcomputer unit 6a are control of the CODEC 3 and the data transfer unit 5 and the like, and can be realized with a relatively simple configuration.

  Next, differences in the roles of the CPU 16 in the conventional digital recorder DR9 shown in FIG. 6 and the CPU 8 and the signal processing control unit 6 in the digital recorder DR1 of the first embodiment shown in FIG. 1 will be described.

  The role of the CPU 16 in the conventional digital recorder DR9 includes overall control of the ODEC 13, control of the data transfer unit 15, control of various interfaces such as GUI, recording data management function, clock management function, and the like.

  On the other hand, the role of the CPU 8 (second microcomputer) in the digital recorder DR1 of the present embodiment includes setting of control parameters for controlling the CODEC 3, control of various interfaces such as GUI, and the like. The CPU 8 executes control of various interfaces such as GUI using the RAM 7, but this control is relatively heavy.

  In addition, the role of the recording microcomputer unit 6a (first microcomputer) in the digital recorder DR1 of the first embodiment includes control of the CODEC 3, control of the data transfer unit 5, recording data management function, and clock management function. .

  As described above, in the first embodiment, the processing performed by the CPU 16 of the digital recorder DR9, which is a conventional system, is transferred to the CPU 8 and the signal processing control unit 6 (recording microcomputer unit 6a) in the digital recorder DR1 of the first embodiment. It is shared. Thereby, in this Embodiment, the burden of CPU8 in the whole system can be lightened at the time of normal recording.

  FIG. 2 is an explanatory diagram schematically showing the operation contents of the CPU 8 and the recording microcomputer unit 6a when the normal operation mode is set.

  As shown in the figure, when the normal operation mode is set, the CPU 8 sets control parameters for the CODEC 3 for the control register group 6b one by one, and the recording microcomputer unit 6a controls the control stored in the control register group 6b. A control signal SC based on the parameters is output to CODEC 3 to control compression processing by CODEC 3.

  FIG. 3 is an explanatory diagram schematically showing the operation contents of the CPU 8 and the recording microcomputer unit 6a when the firmware update mode is set.

  When the firmware update mode is set, since the CPU 8 performs firmware update processing, the control parameters for the CODEC 3 cannot be set in the control register group 6b one by one. Therefore, as shown in FIG. 3, the recording microcomputer unit 6a controls the compression process by the CODEC 3 by outputting the control signal SC to the CODEC 3 based on the control parameter stored in the control register group 6c.

  FIG. 4 is a flowchart showing a processing procedure of firmware update processing in the digital recorder DR1 of the first embodiment. Hereinafter, the firmware update processing content of the digital recorder DR1 will be described with reference to FIG.

  When the process shown in FIG. 4 is executed, there is a preparation for firmware update in which a USB memory (not shown in FIG. 1) storing firmware to be updated is attached to the USB port 10 of the digital recorder DR1. It is assumed that this is done.

  Further, at the stage of the advance preparation, the digital recorder DR1 is in a normal operation mode and performs a normal recording operation. That is, as shown in FIG. 2, the CPU 8 sequentially rewrites the control parameters stored in the control register group 6b, and the recording microcomputer unit 6a generates a control signal SC based on the latest control parameters stored in the control register group 6b. The compression processing by the given CODEC 3 is controlled, and the compressed data D 3 obtained from the CODEC 3 is recorded on the recording device 4 via the data transfer unit 5.

  Referring to FIG. 4, first, in step ST1, CPU 8 sets control parameters for control and setting for CODEC 3 in control register group 6c. That is, the control parameter is set in the control register group 6c to shift to the firmware update mode.

  Next, in step ST2, the CPU 8 sets the information stored in the firmware update state notification register group 6d to “valid”. As a result, the digital recorder DR1 is switched from the normal operation mode to the firmware update mode.

  Therefore, the recording microcomputer unit 6a can recognize the firmware update mode by referring to the information indicating “valid” stored in the firmware update state notification register group 6d. Then, as shown in FIG. 3, the recording microcomputer unit 6a gives a control signal SC based on the control parameter stored in the control register group 6c to control the compression processing by the CODEC 3, and the compression processing obtained from the CODEC 3 is completed. The data D3 is recorded on the recording device 4 via the data transfer unit 5.

  Subsequently, in step ST3, the CPU 8 stops accessing the register groups 6b to 6d, and the CPU 8 updates the firmware by writing the firmware to be updated (control program) in the USB memory into the flash memory 9. Further, the latest firmware (control program) updated in the flash memory 9 is executed.

  Even during the execution of step ST3, the recording microcomputer unit 6a gives a control signal SC based on the control parameter stored in the control register group 6c and hinders control of compression processing by CODEC3 (control when setting the firmware update mode). Can be done without.

  When the activation of the firmware in step ST3 is completed, in step ST4, the CPU 8 sets the information stored in the firmware update state notification register group 6d to “invalid”. As a result, the digital recorder DR1 is switched from the firmware update mode to the normal operation mode.

  Thereafter, in step ST5, the CPU 8 shifts to a normal operation in which control parameters for the CODEC 3 are set in the control register group 6b one by one.

  Therefore, the recording microcomputer unit 6a recognizes the return to the normal operation mode by referring to the information indicating “invalid” set in the firmware update state notification register group 6d after the execution of step ST4. In the execution stage of step ST5, the control signal SC based on the control parameter stored in the control register group 6b can be applied to perform compression control by the CODEC 3, that is, control in the normal operation mode.

  The above is the procedure from the start to the end of firmware update in the digital recorder DR1 of the first embodiment.

  In the first embodiment, an example in which a USB memory is connected to the USB port 10 as a firmware storage medium (means) has been described. However, the firmware storage means is not limited to this, for example, a flash memory, an SD card, or the like. Other storage means may be used.

  In the digital recorder DR1 according to the first embodiment of the present invention, the recording microcomputer unit 6a serving as the auxiliary control unit is a control information storage unit during execution of the firmware update process by the CPU 8 serving as the main control unit. The control parameter stored in the register group 6c is read, and the compression processing by the CODEC 3 is controlled based on the control parameter. Therefore, the compressed data D3 based on the video / audio analog signal S20, which is external information, can be recorded in the recording device 4 without any trouble during the firmware update process.

  That is, since the digital recorder DR1 of the first embodiment has the recording microcomputer unit 6a in addition to the CPU 8, in addition to reducing the processing load on the CPU 8, the CPU 8 can be brought into a free state during the firmware update process by the CPU 8. The firmware update process by the CPU 8 can be executed during the recording of the compressed data D3 by the recording microcomputer unit 6a.

  As a result, the digital recorder DR1 has an effect that it is possible to continuously record the compressed data D3 while updating the firmware without preparing another equivalent digital recorder and performing a replacement operation.

  That is, since it is possible to continuously record the compressed data D3 based on the video / audio analog signal S20 even during the firmware update process of the digital recorder DR1 alone, another digital recorder is prepared for the alternative operation during the firmware update process. There is an effect that can save time and effort.

  The recording microcomputer unit 6a can accurately recognize that the firmware is being updated by referring to the contents (information) of the firmware update state notification register group 6d.

  In addition, the recording microcomputer unit 6a in the signal processing control unit 6 includes the minimum necessary control processing and information management for realizing the recording function among the recording control processing and various information management performed by the CPU 16 in the digital recorder DR9. Is running. Further, the register groups 6b to 6d only store information necessary for the processing of the recording microcomputer unit 6a.

  Therefore, there is almost no increase in cost and space due to the addition of the recording microcomputer unit 6a and the signal processing control unit 6 including the register groups 6b to 6d, so that a low-cost and space-saving digital recorder DR1 can be obtained.

  As described above, since the digital recorder DR1 is constituted by a considerably small hardware system as a whole, the mounting area of components is small, space saving can be realized, and cost merit is great.

  In addition, ASIC etc. are mentioned as a 1st candidate of the device which implement | achieves the signal processing control part 6 (microcomputer part 6a for recording) of this Embodiment.

<Embodiment 2>
FIG. 5 is a flowchart showing a processing procedure of firmware update processing in the digital recorder DR2 of the first embodiment. Hereinafter, the firmware update processing content of the digital recorder DR2 will be described with reference to FIG.

  The configuration of the digital recorder DR2 is the same as that of the digital recorder DR1 shown in FIG. In the firmware update process of the digital recorder DR2, the description of the same processing contents as those of the digital recorder DR1 of the first embodiment will be omitted as appropriate.

  Referring to FIG. 5, first, in step ST11, CPU 8 sets a control parameter for CODEC 3 in control register group 6c. The control parameter includes frame rate information that defines a frame rate for the image-processed digital signal S2 within a predetermined range.

  In step ST11, a control parameter including frame rate information indicating a maximum frame rate (for example, 30 fps (frame per second)) is set. Note that the second frame rate is generally set by the user's designation within a range of about 0.5 fps to 30 fps.

  Thereafter, steps ST12 to ST15 similar to steps ST2 to ST5 of the digital recorder DR1 of the first embodiment are executed.

  As described above, the digital recorder DR2 according to the second embodiment sets the maximum frame rate for the second frame rate specified by the frame rate information in the control parameter set in the control register group 6c during the firmware update process. It is characterized by setting.

  Therefore, the recording microcomputer unit 6a which is the first microcomputer controls the CODEC 3 so that the compression process by the CODEC 3 is performed in the maximum second frame indicated by the control parameter during the firmware update process by the CPU 8.

  Thus, according to the digital recorder DR2 of the second embodiment, during the firmware update process by the CPU 8, under the control of the recording microcomputer unit 6a, which is an auxiliary control unit, from the CODEC 3 to the image-processed digital signal S2 for maximum seconds. By obtaining the compressed data D3 processed at the frame rate, it is possible to record the compressed data D3 including moving image information with high accuracy on the recording device 4.

  For example, when the digital recorder DR2 is applied to a monitoring digital recorder or the like, since the compressed data D3 can be obtained densely in time, when a suspicious person is photographed by the camera 20 during the firmware update process, etc. As the compression-processed data D3 recorded in the recording device 4, there is an effect that the probability of failing to record the person can be kept low.

(Other)
By applying the above-described digital recorders DR1 and DR2 to a monitoring digital recorder that requires continuous operation for 24 hours, the video and audio data being recorded can be accumulated in the digital recorders DR1 and DR2 without being lost. Firmware update processing can be performed. Therefore, video such as suspicious (human) objects can be recorded as compressed data D3 to the recording device 4 without missing, and a robust security system can be constructed.

  In the above-described embodiment, the control register groups 6b and 6c are selectively used in the normal operation mode and the firmware update mode. However, even if one control register group is used, the control parameters are sequentially used by the CPU 8 in the normal operation mode. In order to perform the update, the firmware update mode can be realized by fixing the control parameter.

  The present invention generally relates to a digital recorder that realizes a firmware update process without interruption even during recording of a video or the like.

  1 A / D conversion unit, 2 video processing unit, 3 CODEC, 4 recording device, 5 data transfer unit, 6 signal processing control unit, 6a recording microcomputer unit, 6b, 6c control register group, 6d for firmware update status notification Register group, 7 RAM, 8 CPU, 9 Flash memory, 10 USB port, 20 Cameras.

Claims (3)

A digital recorder for recording data based on external information obtained from outside,
A data compression unit that performs compression processing on the digital signal based on the external information to obtain compressed data;
A data transfer unit that performs a data transfer process for transferring the compressed data and recording the data on a predetermined recording device;
An auxiliary control unit that controls the compression processing by the data compression unit and the data transfer processing by the data transfer unit;
A control program storage unit for storing a control program for controlling main operations of the digital recorder;
A main control unit that executes a main control operation based on the control program, the main control unit can update the content of the control program in the control program storage unit,
The information processing apparatus further includes a shared information holding unit accessible from the auxiliary control unit and the main control unit, and the shared information holding unit includes a control information storage unit that stores control parameters for controlling the compression processing by the data compression unit. Including
The control parameters include first and second control parameters, and the control information storage unit includes first and second control information storage units that store the first and second control parameters,
The auxiliary control unit is configured to store the first control parameter stored in the first control information storage unit by the main control unit during control of at least a data recording operation among the main control operations of the main control unit. Read and control the compression processing by the data compression unit based on the first control parameter, and during execution of the update process of the control program by the main control unit, the main control unit is the second control information Reading the second control parameter stored in the storage unit for controlling, and controlling the compression processing by the data compression unit based on the second control parameter ,
Digital recorder. The digital recorder according to claim 1,
The shared information holding unit further includes a control program update state notification storage unit that stores information on the presence or absence of an update state of the control program,
Prior to the update process of the control program, the main control unit writes information indicating that the control program is being updated to the control program update state notification storage unit,
The auxiliary control unit recognizes that the control program is being updated by referring to the content of the control program update state notification storage unit.
Digital recorder. A digital recorder according to claim 1 or claim 2,
The digital signal includes a video digital signal,
The control parameter includes frame rate information defining a frame rate for the video digital signal within a predetermined range,
The main control unit writes the second control parameter including the frame rate information indicating the maximum frame rate within the predetermined range in the control information storage unit prior to the update process of the control program.
Digital recorder.

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