JPH01169628A - Dynamic replacing system for rom software - Google Patents

Abstract

PURPOSE:To exchange a ROM with a simple constitution by invalidating an original ROM and validating a new ROM when a ROM selecting part is driven. CONSTITUTION:When the stop of an instructed task is discriminated, a pertient task stoppage deciding part 102 outputs a control signal to a ROM selecting part 11 and supplies the control signal to a switching completion display generating part 104. The ROM selecting part 11, when the control signal is received, switches the output condition of a selecting line 110. Then, a ROM 1 and a ROM 2 are driven in the condition opposite to the one until then, the ROM 1 is invalidated, the ROM 2 is validated and the action of the system after that is controlled by the software supplied from the ROM 2. The display to display from the switching completion display generating part 104 of a processing part 10 that the switching is executed is outputted to a display part 14, the display is watched and an operator removes an old ROM 1.

Description

[Detailed Description of the Invention] [(Already needed) Regarding a dynamic replacement method for switching the ROM currently in operation with a ROM with new content in an information processing system in which software is converted into ROM, there is a method for duplicating the devices constituting the system. The purpose of this project is to provide a dynamic replacement method for ROMized software that realizes ROM replacement with a simple configuration, without any need for control programs and application programs.
- In an information processing system in which RAM is stored in a ROM, the processing unit includes a switching command detection unit that detects a switching command that is input when a new ROM in which the contents of an operating program have been changed is attached to the common bus; and a task stop determination unit that starts operation when a switching command is detected, and the task stop determination unit generates a switching control signal when the task of the program to be replaced stops, and also includes a device external to the processing unit that is driven by the switching control signal. The ROM selection section is configured to disable the original ROM and enable the new ROM when the ROM selection section is driven.

[Industrial Application Field] The present invention is an information processing system in which software is converted into a ROM, and the ROM during system operation is converted into a ROM with new contents.
This paper relates to a dynamic replacement method for switching between

In Ift 91 processing system technology, control programs such as O3 (operating system) and various application programs are stored in an auxiliary storage device such as a magnetic disk, and then transferred to RAM (random memory) when the system is started or when needed. access memory)
However, in the case of small-scale information processing systems used in terminals, it is not affected by the environment of the installation location, and it is easy to process at startup (power-on software (including control programs such as O3 and application programs) is stored in ROM (leat-only memory).
There is a system to store it.

An information processing system that uses such ROM as main memory (of course includes a small-capacity working RAM) may be required to change the program (
Situations may occur where it is necessary to change the program (or a table), or when a bald part of a program is discovered and the contents need to be corrected.

In such cases, stop the operation of the information processing system and
You can simply replace the original ROM with a ROM with new content created elsewhere and make it work again, but if the information processing system is required to operate constantly (non-stop), the main memory It is not allowed to stop the system even temporarily to replace a certain ROM. In addition,
Such a request occurs, for example, when data is collected from a constantly (24-hour continuous) monitored or controlled object, or when control data is output.

For this reason, it has been desired to realize a system that allows the ROM storing various programs to be easily replaced without stopping the operation of the system.

[Prior Art] An example of an information processing system equipped with a ROM that stores a control program (O3) and an application program is a terminal device system that is located away from a central computer. The device is connected to the central computer through a communication path, and executes processes such as inputting (or collecting) information around the terminal, transmitting it to the central computer, and outputting data sent from the central computer, using a program.

When installing and operating such an information processing system, if you expand the system or find bald spots, please refer to R.
On the other hand, there has been an increasing demand for non-stop operation of information processing systems, and the method for achieving this is to duplicate the equipment and stop one system at a time when changing the ROM software. A method is used in which the ROMs of both systems are replaced by removing the old ROM and installing the new ROM.

[Problem to be solved by the invention] As described above, in the conventional technology, it was necessary to duplicate the device in order to replace the ROM due to changes in the ROMization software without stopping the system operation. However, having all the equipment duplicated would be expensive and difficult to use.

Therefore, it is conceivable to duplicate only the devices related to the ROM, but there is still a problem that the cost is 1-.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for dynamically exchanging ROMized software that realizes exchanging ROMs with a simple configuration without duplicating the devices constituting the system.

[Means for solving problems] The basic configuration of the present invention is shown in FIG.

In FIG. 1, 10 is a processing section, 11 is a ROM selection section,
12 is ROMI before change, 13 is ROM2.1 after change
4 represents a display section, and 15 represents an input section.

The processing unit 10 includes a switching command detection unit 101, a corresponding task stop determination unit 102, a task management unit 103, and a switching end display generation unit 104.

Note that some programs in the changed ROM 2 are changed from those in the original ROMI, and addresses other than the program to be replaced (changed) among the programs made up of a plurality of modules are not moved.

In the present invention, when the changed ROM2 is inserted into the system while the system is operating with the ROMI before the change, and a switching command indicating the program to be replaced is input, whether the task of the program to be replaced is stopped or not. The judgment operation starts, and when a stop is detected, the ROM
An output is given to the selection section, and by the operation of the ROM selection section, R
The ROM is replaced by stopping the output of OMI and generating the output of ROM2.

[Operation] When ROMI, 12 (hereinafter simply referred to as ROMI) is operating effectively, ROM2 with a changed program is installed. In this case, by the output of the ROM selection section 11, R
OMI is selected and generates an output, and ROM2 is inhibited from outputting.

Next, when a switching command (including content instructing the change program to be replaced) is input from the input unit 15,
The switching command detection unit 101 of the processing unit 10 detects this and generates a detection output. Upon receiving this detection output, the corresponding task stop determination unit 102 starts operating, and the task management unit 10
It is determined whether the instructed task has stopped by looking at the task operation status in step 3 (each task operates periodically and stops at each cycle).

When determining whether to stop the instructed task, the corresponding task stop determination section 102 outputs a control signal to the ROM selection section 11 and also supplies a control signal to the switching end display generation section 104 . Upon receiving this control signal, the ROM selection section 11 switches the output state of the selection line 110.

Then, ROMI and ROM2 are driven to the opposite state, ROMI is disabled and ROM2 is enabled, and the subsequent operation of the system is controlled by software supplied from ROM2.

Further, the switching completion display generation unit 104 of the processing unit 10 outputs a display (message, etc.) indicating that the switching has been executed to the display unit 14. Remove ROMI.

[Example] The configuration of an embodiment of the present invention is shown in FIG. 2(a).

In FIG. 2 (al), 20 is a central processing bag W (hereinafter simply referred to as CPU), 21 is a keyboard/display section, 22 is an ink face circuit, 23 is a ROM unit selection circuit,
24 is the ROM Unisol l-A before the change, 25 is the R after the change
OM unit B 126 is a small-capacity RAM used as a work area for program execution, 27 represents an I10 ink face circuit, and 28 represents an I10 device.

Note that when multiple program modules xXy, z are stored in ROM unit B (before change), the program modules in ROM unit B (after change) are X', Y
, Z, the rough 1-ware addresses other than X are not moved. Then, when a change is made such that the memory area occupied by X, which is the software to be replaced, is increased, X' is relocated to a rear empty area.

The devices or circuits shown in FIG. 2(a) are connected to each other by a system bus, and the bus consists of a data bus 201 and an address bus 202 including control lines.

FIG. 2 (bl) shows an explanatory diagram of the ROM unit replacement procedure according to the present invention, and this diagram will be explained.

First, the program is modified (30), a new ROM unit B is created according to its contents (31), and the created ROM unit B is then connected to the system bus as shown in Figure 2 (a). Connecting. In this case, the ROM unit B is inserted into a spare slit that is normally provided in the information processing system (32).

After inserting the ROM unit B, input a command to switch the program from the keyboard of the keyboard/display unit 21 shown in FIG. Performs switching processing (34), and displays a switching completion indication on the keyboard/display unit 21 upon completion of switching (35)
. By outputting this display, the operator can
Remove M unit 8 from the slit (36).

Next, the contents of the switching process (34) in the procedure of FIG. 2 (bl) will be explained using the switching process flow shown in FIG. 2 FC.

First, identify whether a switch command has been submitted,
If it has been inserted, the status of the software to be replaced is retrieved (41). The state of this software is determined by extracting the state of the relevant task from the task management unit (○S: under the control of the operating system) using the O8 system call and determining whether it is in a stopped state or not (
42).

As a result, if the replacement target software has not stopped, standby (processing indicated by the dotted line from 42 in Figure 2 (C))
or force it to stop. If a stop condition is detected,
Outputs a switching instruction to the ROM unit selection circuit 23 (4
4). Specifically, this instruction output is given on the system bus, and the address specified by the ROM unit selection circuit 23 is output to the address bus (part of 202), and a part of the data bus 201 is used to output switching data. A signal is supplied and a write instruction is given to the control line (part of 202).

Upon receiving this switching instruction, the ROM unit selection circuit 23 in FIG. 241 and 251 to disable and enable the respective units.

When the ROM units are replaced in this way, the replacement target rough 1 to wear are initialized with new contents (45).

Following this, a process is executed to transfer the data of the switching end message (contents set in advance) to the keyboard/display unit 21 as a designated address (46), and this series of processing routines is completed.

Figure 3 shows the ROM unit selection circuit 2 in Figure 2 (al).
A specific configuration example of No. 3 is shown below.

In FIG. 3, reference numeral 40 represents a selection switch (represented by SW) at the time of Yesial, 41 represents an R'OM unit selection circuit, 42 represents a register (flip-flop circuit), and 43 represents an address decoder.

When only the ROM unit A is initially mounted, the selection switch 40 is left open. Then, at the initial time (power ON), that is, when the reset control line (701) becomes logic "0", the clear terminal (CLR) of the register 42 is driven by the logic operation of the gate circuit, and the output terminal Q outputs a logic “o”. This output is R'
It is detected by the unit selection determination section 241 of the OM unit Δ (see FIG. 2(a)), and enables the connection between the ROM unit and the system bus.

Next, when the changed ROM unit B is inserted into the slit, the selection determination unit 251 of this Uniso I-B indicates that the selection output is "'0", so it is not selected, so the connection with the system bus is disabled (off). Make it.

After that, when a switching command is input, a switching instruction from the CPU is output to the bus.

At this time, each bus has address buses AO to /1. n outputs an address specifying the ROM unit selection circuit 41, and the data line of the data bus (in the example of FIG. 3, D
Selection data "1" (Do pin l-) is output to the O pin (using only the O pin), and the write control line 1oWR among the control lines is further driven.

Then, the contents of the data value Do (“1”) are supplied to the data terminal of the register 42, and the address decoder 43 decodes the address information and detects that it is the preset own address and outputs it. The signal of the SR processing signal write control line oWR is sent to the NOR circuit 44.
The signal is supplied to the clock input of the register 42 through the input signal 42, and acts as a timing signal for setting the data terminal signal "1" in the register 42.

In this way, 1'' is sent to the register 42, and the selection output 420 becomes ``1'' and is output from the output terminal Q of the register 42.The selection output 420 is output from the selection determination unit 241. 251 and the selection determination unit 24
1 detects that it is not selected and disables the ROM UniSo I-A (cuts the connection with the system bus), and the selection determination unit 251 detects that it is selected and disables the ROM UniSo I-A. enabled and virtually connected to the system bus
Combined with PU.

[Effect of the invention] RO can be performed using an information processing system equipped with ROM software.
When changing M, the ROMized software can be dynamically replaced while the system continues to operate and without duplicating devices. Furthermore, with this simple configuration, non-stop operation of the apparatus can be achieved.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the principle configuration of the present invention, FIG. (C) is a diagram showing a switching processing flow, and FIG. 3 is a diagram showing a specific configuration example of a ROM unit selection circuit.In FIG. 1, 10: Processing section 11: ROM selection section 12: ROM1 before change 13; ROM2 after change 14: Display section 15: Input section

Claims (1)

[Claims] In an information processing system in which a control program and an application program are stored in a ROM (12), the processing unit (10) attaches a new ROM (13) in which the contents of the currently operating program are changed to the common bus. A switching command detection unit (1
01) and a task stop determination unit (102) that starts operation when a switching command is detected.
02) generates a switching control signal when the task of the program to be replaced stops, and also provides a ROM selection section (11) outside the processing section (10) that is driven by the switching control signal, and the ROM selection section ( 11) is a dynamic replacement method for ROMized software, which is characterized in that when driven, the original ROM (12) is invalidated and a new ROM (13) is activated.