JPH0548496B2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Technical Field The present invention relates to a data processing device connected to an external storage device, and in particular, to a data processing device that automatically dumps memory contents to a program storage section in the external storage device when a failure occurs. Related to data processing devices such as ATMs.

(b) Prior art and its disadvantages When an ATM starts up, it first loads a predetermined program from an external storage medium such as a floppy disk using the iPL program stored in the system's ROM, and then controls the program after the loading is complete. Move to the start address of the loaded program. Furthermore, when the device malfunctions or the system goes down due to a program bug, equipment abnormality, etc., the entire memory contents at that time are dumped to the external storage medium used for program loading unless the cause is immediately determined. The cause is investigated by analyzing the contents dumped on the external storage medium.
However, the problem in this case is that the external storage medium to which the memory is dumped is the same as the external storage medium on which the program was loaded, so the operator may mistakenly set the external storage medium after the memory dump has been performed at system startup. This is something that could happen. In this case, the system will definitely malfunction, leading to improper handling of money or even harm to humans.

(c) Purpose of the Invention The purpose of the present invention is to provide data processing with a memory dump function that prevents the program loaded into memory from running even if an external storage medium on which memory has been dumped is accidentally set at system startup. The goal is to provide equipment.

(d) Structure and Effects of the Invention In summary, the present invention can be summarized as follows: When dumping memory, the content of the execution start address of the dumped program is replaced by an instruction that does not allow the program to proceed forward, such as a branch instruction to the execution start address itself. or
It is characterized by providing a means to replace it with a HALT command or the like.

By configuring as described above, according to the present invention, even when the content that was mistakenly dumped in memory is loaded and executed again, the start address of the program to which control is transferred after loading is completed, the execution starts. A branch instruction to the address itself
Since the program such as the HALT instruction is replaced with an instruction that does not proceed any further, the program will not be executed any further, and malfunctions of the entire system can be prevented. As a result, when applied to an ATM or the like, for example, it is possible to prevent improper processing of money or harm to the human body.

(e) Embodiment FIG. 3 is a block diagram of an ATM that is an embodiment of the present invention. CPU1 has automatic teller machine 2,
A RAM 3 for storing programs and data, a ROM 4 for storing iPL programs, and an FD drive device 5 for driving a floppy disk are connected. When the floppy disk storing the program is set in the FD drive unit 5 and the power is turned on, the iPL stored in the ROM 4 is
The program runs and loads the program from the set floppy disk to RAM3. As soon as the loading is complete, CPU1
Control is transferred to the start address (execution start address) ST of the program loaded into RAM3. That is, set the program counter to the start address ST,
Automatically start loaded programs. Thereafter, transactions are performed in the automatic teller machine 2 by executing the program.

FIG. 4 shows the correspondence between the storage contents of the floppy disk and the address space of the memory. When the power is turned on, the CPU 1 is controlled by the iPL program stored in the ROM area, and by executing the iPL, the program stored in the floppy disk is loaded into the RAM area. When the loading is completed, control of the CPU 1 is transferred to the start address ST of the RAM area. Since the start address is the execution start address of the loaded program, the system will thereafter operate based on this loaded program.

When the automated teller machine 2 malfunctions or the system goes down for some reason, and the cause cannot be immediately determined, the command at the execution start address ST is directly or indirectly branched to the execution start address itself. Replace it with the instruction and dump the data in all memory spaces except the ROM area to the floppy disk as is. still,
The dump program is loaded from the floppy disk when loading the iPL, and is stored in the RAM area along with the system program, utility program for automatic cash transactions, etc. Therefore, when dumping memory, this dump program directly or indirectly replaces the instruction at the program execution start address ST with a branch instruction to the execution start address itself, and then transfers all data in the RAM area to the iPL of the floppy disk. It has a function to dump memory to the same location as when loading. Figure 5 shows the connection between the floppy disk and memory.
Shows data movement during iPL loading and dumping.

FIG. 1 is a flowchart showing the operation when dumping memory, and FIG. 2 is a flowchart showing the operation when iPLing the dumped floppy disk.

At the time of memory dump, in step n1, the start address of the program, that is, the execution start address
Replace the contents of ST with a branch instruction to the execution start address itself. Next, in step n2, the entire contents of the memory space (all RAM areas) except for the iPL program (excluding the ROM area) are dumped to the floppy disk, and the process ends.

When performing iPL on the dumped floppy disk, first, in step n10, the contents of the floppy disk (including programs and data) are loaded into the RAM area. Subsequently, in step n11, control is transferred to the execution start address in the RAM area, and the CPU 1 executes the instruction at that address. In this case, since the instruction stored at the program start address, that is, the execution start address ST, is a branch instruction that branches to the execution start address itself, the branch instruction is executed continuously at n12. That is, the program will not run any further.

By performing the above operations, it is possible to prevent the system from malfunctioning even if the floppy disk on which the memory was dumped is accidentally inserted and iPL is loaded.
Note that in the above embodiment, a branch instruction that branches to the execution start address itself is used as an instruction that does not allow the program to proceed forward; however, instead of this,
It may also be a HALT command or other similar commands.

[Brief explanation of the drawing]

Figure 1 is a flowchart showing the operation of memory dumping in an ATM which is an embodiment of this invention, and Figure 2 is a flowchart showing the operation of memory dumping in an ATM that is an embodiment of this invention.
A flowchart showing the operation when loading and executing, Figure 3 is a block diagram of the ATM, Figure 4 is
FIG. 5 is a diagram showing the comparison between the contents of the floppy disk and the memory space when loading iPL, and FIG. 5 is a diagram showing the movement of data between the floppy disk and the memory.

Claims (1)

[Scope of Claims] 1. A data processing device connected to an external storage device, comprising: program loading means for loading a program stored in the external storage device into a memory inside the data processing device; A program execution means for executing a loaded program; and a program execution means for replacing an instruction in an execution start part of the program loaded into the memory inside the data processing device with an instruction that does not allow the execution of the program to proceed when a failure occurs. A data processing device comprising: means for overwriting and memory dumping a program into a program storage portion in the external storage device.