JPS61136345A - Data transmission system - Google Patents

Abstract

PURPOSE:To change the processing of a firmware without changing the contents of a stored firmware by making an address branch to a specified address, when said address by which a data transmission equipment executes an access to the firmware coincides with a set value. CONSTITUTION:When a data transmission equipment is executing and processing a micro-instruction, if a value of a micro-instruction address register MAR31 of a processor 22 of the inside becomes a value of a coincidence address register 32 which is set by other transmission equipment, a selector 39 selects forcibly a constant 38, and sets it to a micro-instruction register 40. When the constant 38 being its micro-instruction is executed, a microprogram control circuit 41 hits the head address of a firmware written in a RAM36 by a specified command, to the MAR31 and executes it. Also, when a series of addresses is executed, the address is made to branch to a firmware to be executed, by a micro- instruction stored in the firmware.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a data transmission system having a transmission path for transmitting information and a plurality of data transmission devices connected to this transmission path and performing all of the above-mentioned information transmission and reception. Regarding the replacement of firmware by command, is it possible to process 7 arm squares without changing the contents of the firmware stored in advance? It's about data transmission methods that can be changed.

[Conventional technology]

Conventionally, in pigeonholes that replace this type of firmware, generally each data transmission device is a 7-arm square TC connected to a floppy disk device, a cassette magnetic tape, a magnetic tape, or other storage device that can be directly written to.
! - A method is used to do this.

[Problem that the invention seeks to solve]

In the above method, the firmware is loaded onto a directly writable storage device, so in order to make any changes to the firmware, it is necessary to completely air the original firmware, and it is necessary to completely air the original firmware before changing the firmware. However, there are problems in that it is difficult to manage the device and change the address while the system is in operation due to a 1-shift change in the address after the change.

In recent systems, an increasing number of data transmission devices are equipped with firmware that is entirely direct read-only memory (CPROM) in order to reduce costs. However, in order to change the firmware, the FROM must be changed, which has the disadvantage of requiring a large amount of man-hours.

[Means for solving problems]

In view of the above points, the present invention has been devised to solve all of these problems and eliminate such drawbacks, and its purpose is to bypass normal data transfer without changing the pre-stored firmware. We propose a data transmission device that can change firmware processing in the same way.
I'm going to offer it.

In order to achieve all of these objects, the present invention provides means for loading firmware from a first data transmission apparatus to a second data apparatus via a transmission path, and a setting means for setting an arbitrary value. In preparation, when the second data transmission device running the firmware sets the address to which the firmware all accesses and the next value matches the next value, the second data transmission device then branches to a specific address. 6 principles of firmware pre-installed in
fI: Disabled so that firmware at the branch destination can be executed, and when a specific command is sent from a first data transmission device to a second data transmission device, the second data transmission device The address for accessing the firmware is set by the setting means so that it includes a method Re that does not branch even if it matches the friend value.

[Effect]

By setting an address to access the firmware and an arbitrary value, the function of branching to a specific address when it matches the t value can be done without changing the pre-built-in firmware by an external command.
The firmware process is completely changed in the same way as normal data transfer.

C*Example] Embodiments of the present invention will be described in detail below based on the drawings.

FIG. 1 is an explanatory diagram showing an example of a data transmission system to which the present invention is applied.

In order to facilitate understanding of the present invention, this will be explained first.

In the figure, 1, 2...4 are data transmission devices, and 11, 12...φ14 are data transmission devices 1 to 4, respectively.
This data transmission system includes a plurality of data transmission devices 1 to 4 and loop transmission lines 11 to 14.
It consists of

FIG. 2 is a block diagram showing one embodiment of the present invention.

In FIG. 2, parts corresponding to the same reference numerals as in FIG. Processor 22 data bus 23. The transmission line control circuit 21 ft is composed of a signal line group 241 for transmitting control signals for controlling an interrupt, and an interrupt line 25 for sending the interrupt to the processor 22 .

A block diagram showing an example of the configuration of the processor 22 in the embodiment of the second factor is shown in the third part.

In FIG. 3, corresponding parts are shown with the same symbols as in FIG. 2, and 31 is a microinstruction address register (hereinafter referred to as
(referred to as MAR), 32d Match address register (hereinafter referred to as C
33 is the output of MAR31 and CAR3
This comparison circuit 33 compares the outputs of M
When the output of AR31 and the output of CAR32 match, a match signal cBt- is generated.

Reference numeral 34 denotes a t-th start-up flip-flop for validating this match signal as; 35 an AND circuit that inputs the output of this start-up 7 flip-flop 34 and the match signal as from the comparator circuit 33, and calculates the logical product of the two forces; 36; 37i is a writeable and readable storage device (hereinafter referred to as RAM), a storage device exclusively for 37i storage (hereinafter referred to as ROM), and 38 is a value indicating the contents of the plastic/chip microinstruction (
39 is a selector, 40 is a microinstruction register (hereinafter referred to as MIR) which receives the output of the selector 39, and 41H is a microphone α program control circuit.

115m indicates a select signal supplied from the MAR 31 to the selector 39, and onl and oD are signals sent from the RAM 36 and the ROM 37 to the selector 3, respectively.
9 shows the output data supplied to 9.

FIG. 4 is an explanatory diagram showing a general frame format applied to the present invention.

A typical frame flowing through the transmission paths 11 to 14 (see Figure 1) includes a flag pattern F indicating 01111110't-, a destination address DA indicating the destination address,
It consists of a source address SA indicating the address of the source, control information C, data information I, and a check bit FC8 that performs a cyclic redundancy check in a frame check sequence.

Note that the above data information processing may be omitted as part of the frame configuration.

Next, it is shown in Figure 2! i! The operation of the embodiment will be explained with reference to FIGS. 1, 3, and 4.

Now the 11th! Assume that the data transmission device 4 shown at i0 has to make changes to a specific processing routine relative to the data transmission device 1.

First, the data transmission device fjt4 converts the content including the firmware into the frame format shown in FIG. 4 to be changed, and transmits it to the data transmission device 1 as a command A. When the transmission line control circuit 21 (see FIG. 2) of the data transmission device 1 receives the 7th frame of command A, it writes the frame to a buffer (not shown) in the transmission line control circuit 21 and interrupts the interrupt line 25. A signal is generated and notified to processor 22.

Next, the microprogram control circuit 41 shown in FIG. 3 in this processor 22 uses an interrupt signal to connect the buffer in the transmission line control circuit 21 shown in FIG. The control information Ct in the frame shown above is read and interpreted by a command person, and further,
Data information It stored in the frame is written to the RAM 36 via the signal line group 24 and the take bus 23t, and the command A
All operations are completed. Hereinafter, the firmware written in the RAM 36 will be referred to as firmware F in this embodiment.

In this way, the data transmission device 4 is connected to the data transmission device 1.
After writing the firmware to the RAM 36, the CAR 32 and startup flip 7c in the data transmission device 1
Send the information command At that you want to set to the r-button 34 and send it to the data transmission device 1 using the same method as in the previous example.

Then, the transmission path control circuit 21 (second
When the command B (see cause) receives all frames of command B, it generates an interrupt signal on the interrupt line 25 and notifies the processor 22.

The microprogram control circuit 41 in the processor 22 accesses the transmission line control circuit 210 by an interrupt signal, reads the control information Ct in the frame, interprets it as command B, and reads the data information in the frame. To the CAR 32 through the signal line group 24 and the data bus 23t,
A value specified by F (hereinafter referred to as X in this embodiment) is set in the data transmission device 4 (hereinafter referred to as X) yt in the CAR 32, and a logical value 1t- is set in the start-up flip-flop 34, and the operation of command B is completed.

Then, the data transmission device 1 has a startup flip 70 and a knob 34.
When set to , the MA during the original microinstruction execution process
The value of R31 becomes the value of X. Then, the match signal CS obtained on the output signal line of the comparison circuit 33 turns on, and the select signal 1581 obtained on the output signal line of the AND circuit 35 turns on, so that the selector 39 is forced to select the constant 38 gold. and is set to MIR40.

Furthermore, when the microprogram control circuit 41 executes the microinstruction (constant 389t), the command A is written to the RAM3B by the MAR31 and the next firmware F
The first address of firmware F is set, and thereafter the firmware F
is executed. Then, when a series of 7 arm square F is executed, among the firmware stored in advance,
Branch to the firmware that should be executed. Note that this branching microinstruction may be placed at the end of the firmware F. tfc1 If there is no need to return to the previously stored firmware, there is no need to include it at the end of the branching microinstruction t-firmware F.

That is, the data transmission device 4 changes the firmware pre-stored in the data transmission device 11 so that the firmware F written in the data transmission device 1 will be executed as a replacement for the firmware that needs to be changed. There's no need.

Next, when it is necessary to completely change the firmware of the data transmission device 1, this can be accomplished by sending the command Dt from the data transmission device 4 to the data transmission device 1. When this command Dt is received by the transmission line control circuit 21 (see FIG. 2) in the data transmission device 1, it generates an interrupt signal on the interrupt line 25, and the processor 2
Let 2 know. Then, the microprogram control circuit 41 in the processor 22 of q reads the contents of the frame via the data bus 23t in response to the interrupt signal, reads the control information Ct in the frame, interprets it as a command D, and activates the activation flip-flop. 34t-Reset, the processing of command D ends. Therefore, from now on MAR31 and C
Even if the values of AR32 match and become 9, the select signal (match signal) 881 on the signal output line of the AND circuit 35 is no longer generated, and the value of the constant 38 is no longer set to MIR40.

For example, when a specific command is sent from the data transmission device 4 to the data transmission device 1, the address from which the data transmission device 1 accesses the firmware is set by means of setting an arbitrary value, and the address matches the value set by the means for setting an arbitrary value. I don't even have brunch.

In the above-mentioned example, the explanation was given from the side of the pigeonhole to the data transmission device via the loop-shaped transmission line, but the present invention is not limited to this. For example, as shown in FIG.
The data transmission device 51 connects the data transmission device 52 to the transmission line 51.
There is a method for transmitting information via a transmission line 611, as shown in FIG. , the data transmission device 711 is connected to the data transmission device 7.
12 and data transmission device 71
1 transmits information to the data transmission device 721 (the processing of the data transmission device during command transfer is only to convert the command, everything else is the same as in the above example), etc. All are included in the present invention.

Note that 63.64 in FIG. 6 above indicates data transmission devices, and 71 to 78 and 713.722 to 713.722 in FIG.
723 is a data transmission device Kaneko.

Although the present invention has been described above by taking as an example a method using 7-frame transfer on a transmission path, the present invention is not limited to this, and can be applied to any interface, including internal paths within the device. Needless to say.

〔Effect of the invention〕

As explained above and as follows, according to the present invention, the function of branching firmware to a specific address when it matches the address to be accessed can be performed by an external command without changing the contents of the firmware stored in advance.
Since the firmware processing can be changed, the practical effect is extremely large.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing an example of a data transmission system to which the present invention is applied, Fig. 2 is a block diagram showing an example of the present invention, and Fig. 3 extracts the part related to the processor in Fig. 2. FIG. 4 is an explanatory diagram showing a general frame format applied to the present invention, and FIGS. This is an explanatory diagram showing another example of the data transmission system. 1-4...φ fist data transmission device, 11-14...transmission line, 21...transmission line control circuit, 22...bone processor, 3111111 microinstruction address register, 32... -97) “Iz register, 33・Φ
Φ・Comparison circuit, 34...φ starting 7 rig 7C2 tube,
35...AND circuit, 36.37...Storage device, 38eφ/constant L39...Q selector, 40...
Φ Microinstruction register, 4111--Microprogram control circuit, 51.52.61-64.71-78
...Data transmission device, 511, 611 ・ Legs
・Transmission line, 711-713, 721-723 @・-・
Data transmission equipment.

Claims (2)

[Claims] (1) In a data transmission system having a transmission path for transmitting information and a plurality of data transmission devices connected to this transmission path for sending and receiving the information, a first data transmission device among the plurality of data transmission devices The device includes means for loading firmware from the device to the second data transmission device via the transmission path, and setting means for setting an arbitrary value, and the second data device executing the firmware is configured to load the firmware to the second data transmission device. When the address to be accessed matches the value set by the setting means, a branch is made to a specific address, and from then on, processing of the firmware built in the second data transmission device is disabled, and the firmware at the branch destination is A data transmission method characterized by being able to execute. (2) In a data transmission system having a transmission path for transmitting information and a plurality of data transmission devices connected to this transmission path for sending and receiving information, from a first data transmission device among the plurality of data transmission devices. the second via the transmission path.
means for loading firmware into the data transmission device; setting means for setting an arbitrary value; and when a specific command is sent from the first data transmission device to the second data transmission device, the second data transmission device 1. A data transmission system, comprising means for not branching even if an address from which a device accesses firmware matches a value set by the setting means.