DE2717375C3 - Device for locating program or hardware errors - Google Patents

Description

The invention relates to a device of the type specified in the preamble of claim 1.

In data processing devices, which are now often controlled by microprocessors, can In addition to errors in operation, errors also occur because either the stored program (e.g. user program) is incorrect or that the memory has errors (ζ. e.g. because the cells of a integrated memory chips are not flawless).

In all of these cases, processing by the device either leads to incorrect results or a Error lamp indicates the occurrence of errors without the operator being able to recognize whether the Errors caused by the machine or due to an operator error originated. The operator must therefore carry out the machining process repeatedly check whether there was no operator error. Is it determined in this way that a program or If there is a hardware failure, it is necessary to remove the memory chips from the machine - for example Booking machine, Invoicingautoir.at, text processing device or similar - can be found and in a special Check test device step by step from the first to the last memory location.

From "Reviews of Input and Output Equipment Used in Computing Systems", Joint AIEE-IRE-ACM Computer Conference, March 1953, See 78 and 79, it is known to diagnose errors and locate Error points to provide a control and display panel that has a large number of error indicators, status lamps and control means for obtaining diagnostic information. For example

ίο the status of various assemblies and circuits, Steps in the arithmetic process, addresses, etc. are represented. It's one in hers Expenditure for a large computer justifiable error checking system, which for smaller, microprocessor-controlled Data processing equipment would be neither suitable nor even applicable in the proposed way.

From DE-OS 24 15 555 a device for determining the location of the fault for smaller, microprocessor-controlled Devices of data processing known in which the transmitted from the memory with the help of check bits Information can be checked for parity under control by the processor. Will be a mistake is established, the address of the functional unit triggering the error is displayed on a lamp field shown, which serves to display the operating status of the device in the event of a non-error. This facility offers the possibility of utilizing existing components without major equipment expense to immediately recognize the occurrence of an error and to localize the faulty module.

The assembly can thus be exchanged for another assembly, but is then in turn, a separate and additional fault locator is required to locate the exact fault location within to find the discarded assembly.

The invention is based on the object of providing a possibility in devices of the type mentioned above Detection of program or hardware errors in the memory and for the exact localization of the error location to create without a great structural effort or additional equipment would be required.

According to the invention, this object is achieved by the features specified in the characterizing part of claim 1 solved.

The advantages achieved by the invention are in particular that a simple means The possibility has been created to determine immediately if an error occurs whether it is a Control panels has acted, and - if it is a program or hardware error - without Search effort to immediately determine the exact location in the memory that is faulty.

An embodiment of the invention is shown in the drawings and will be described in more detail below explained. It shows

Fig. Ι a block diagram of a dalenverarbeitenden Device and

F i g. 2 is a flow chart.

In Fig. 1 the essential for explaining the invention are functional blocks of a dalenverarbeitenden Device, for example a Fakiurierautomat shown. An input keyboard 1, a printer 2, a controller 3 and a memory 4 are available via a data bus 5, an address bus 6 and a control bus 7 with each other in conductive connection. Control 3 and memory 4 are part of a microprocessor (or Microcomputers), the memory consisting of a ROM or PROM, a RAM or both

27 M375

can. All other assemblies known to be contained in a microprocessor, such as. B. Register, battery, ALU, etc., are not shown in detail because of the better understanding, but as a component of the blocks control 3 and memory 4. A lamp field 8, which should be provided with 8 lamps, is also controlled by the controller 3, the values to be displayed in a lamp register 9 in the Control are provided. Furthermore, an error lamp 10 is provided, which when a Program or hardware error is also controlled by the controller 3. It can be act the usual in known devices error lamp to display an operating error, the display An operator error lights up constantly while it flashes to indicate a program or hardware error. However, separate lamps can of course also be used. On in the control 3 The instruction counter 11 contained therein is used in a known manner for the sequential addressing of microinstruction sequences in memory 4, which are read from memory during a program run.

With the aid of the flow chart in FIG. 2, the functionality should be explained below when a program or hardware error occurs. A stored command list contains all commands permissible for the various microprogram sequences, which in the present example each consist of 8 bits. Every single command “A” of a running microprogram is compared with the commands “B” stored as a command list. A positive comparison result means that the execution of the program continues without interruption. A negative comparison result, however, has the consequence that a special error display program is activated. This first causes the error lamp 10 to be activated so that the operator becomes aware. In the further course of the process, the memory content addressed by the command counter at the time of the error (= command consisting of 8 bits) is written into the lamp register 9 and displayed in the lamp field 8. The 8 lamps of the lamp field thus show the current code combination of the addressed memory location.

The operator is now able to help a printed list of commands or a printed program to determine where the Error is located.

In order to be able to page back or forwards in the memory, a key »V« and a key »R« are arranged in the keyboard - To be able to localize combinations or in cases where the error occurred a few program steps earlier but was not recognized because the faulty code combination was still a permissible command that only subsequently led to noticeable errors.

If the "V" key is pressed, the address of the command counter 11 in the controller 3 is increased by the value +1, while if the "R" key is pressed, the address is decreased by the value 1. The command addressed by the changed address is now written in the memory 4 into the lamp register 9 and displayed as a code combination by the 8 lamps in the lamp field.

The special display program now continuously asks the "V" and "R" keys whether they have been actuated. If the error has been located and further display of the commands in the lamp field 8 is no longer required, a key "C" is pressed, which causes the error lamp 10 to go out and a return to the program.

Instead of the list of permissible commands on which the example described is based, which are used as a comparison list is stored in the device, the complete or individual program sequences can of course also be used as a comparison list must be present, as well as other features of the programs suitable for error checking. Likewise, the idea of the present invention also includes solutions in which the display of the Commands on the lamp field are only triggered after pressing a button once or several times, where so z. B. after the error lamp lights up, buttons must first be pressed. It is still It is conceivable that the command addresses before the commands are displayed - also possibly key-controlled - displayed by the lamps. If the number of address or command bits is greater than that number of lamps provided, the representation of an address or a command in the lamp field can of course also take place in several stages.

For this purpose 2 sheets of drawings

Claims (3)

Patent claims: 1. Device for locating program or hardware errors in memories of processor-controlled, micro-programmed data processing devices, in which the control system continuously checks the data for correctness during processing, with a lamp field that can be operated via a lamp register and that is in the non-error Trap to display the operating status of the device and, in the event of an error, to display the error location, characterized in that each byte of a program transferred from the memory (4) to the data lines (5) for processing to the controller (3) simultaneously with a second part the memory (4) transferable bytes of a list of permissible codes ^; In the circuits of the controller (3) it is comparable that if they agree, the checked program can be released for further processing and, if they do not match, it can be transferred to the lamp register (9) for binary representation by the lamp field (8). 2. Device according to claim 1, characterized in that in addition to the lamp field (8) a Another lamp (10) is provided, which is triggered by the circuits of the controller (3) in the event of a mismatch of a program byte can be activated with the bytes of the list of permitted codes. 3. Device according to claim 1 or 2, characterized in that operating elements are provided are, when actuated, signals can be transmitted to the circuits of the controller (3), one of which Increase or decrease the program byte which is shown on the lamp field (8) Address by +1 or -1, reading out the neighboring program byte that can be addressed with it from the memory (4) and its transmission via the data lines (5) to the lamp register (9) for binary representation through the lamp field (8) can be triggered.