JPH03260748A - Connection defect display circuit - Google Patents

Abstract

PURPOSE:To display the occurrence of a defective connection of a cable regardless of the working of a processor by providing a transfer means to transfer the output of a detection means directly to a display means. CONSTITUTION:A detection means 19 detects a defective connection of a cable 4 via a connector 9 and outputs a status signal to a transfer means 21 to show the defective connection. The means 21 transfers the status signal directly to a display means 22 to display it there. Thus the means 19 that detected the defective connection of the cable 4 can display a status on the means 22 to show the defective even though no program is loaded to a storage means 20 from another printed board unit due to the occurrence of the defective connection of the cable 4 and a processor 13 is unable to work.

Description

[Detailed Description of the Invention] [Summary] In a device that operates by connecting a plurality of printed board units with cables, when a connection failure occurs in the cables,
Regarding connection failure display circuits that can reliably display connection failures, the purpose of this circuit is to display the occurrence of cable connection failures regardless of the processor's operation. A storage means into which a program is loaded, a processor that reads the program loaded into the storage means and operates, a detection means that detects a cable connection failure and notifies the processor, and displays the status collected by the processor. In the printed board unit equipped with a display means for detecting, a transfer means for directly transmitting the output of the detection means to the display means is provided,
When a connection failure occurs in the cable, the detection means directly causes the display means to display a status indicating the cable connection failure.

[Industrial application field]

The present invention relates to a device that operates by connecting a plurality of printed board units with a cable, and more particularly to a connection failure display circuit that can reliably display a connection failure when a cable connection failure occurs.

In recent years, with the spread of small, high-performance personal computers, etc., small-sized, large-capacity magnetic disk devices used as external storage devices have also come into use.

In such a magnetic disk drive, multiple printed board units are attached to a disk enclosure that seals the magnetic disk, spindle motor, access arm, voice coil motor, etc., and these printed board units are connected with cables to transmit signals. The device is configured to operate as a magnetic disk device by sending and receiving information.

In this way, the cable that connects printed board units usually has connectors at both ends, and is connected to a circuit formed on the printed board units by means of the connectors.

Therefore, since a cable connection failure is expected due to insufficient insertion of the connector, etc., a connection failure display circuit is installed that checks the cable connection and displays an error when a connection failure occurs due to connector removal, etc. However, it is necessary to ensure that the information is displayed when a connection failure occurs.

[Conventional technology]

FIG. 3 is a block diagram illustrating an example of the prior art.

In FIG. 3(a), a printed board unit 1 has a function of controlling each part of the device, and a printed board unit 2 has a function of controlling an interface signal with a host device 3. In FIG. The printed board units 1 and 2 are connected by a cable 4 to exchange necessary signals.

Further, the printed board unit 2 is connected to the host device 3 by a cable 5, and an interface signal controlled by the circuit inside the printed board unit 2 is sent to the host device 3.
Signals sent from the host device 3 are received by the printed board unit 2 via the cable 5.

3 to 3) show only the circuits related to the poor connection indicating circuit of the printed board unit 2.

When the power is turned on, the processor 7 of the printed board unit 1 reads the program stored in the ROM 6 and operates, and the processor 7 of the printed board unit 1 reads the program stored in the ROM 6 and writes the program to the RAM 12 of the printed board unit 2 via the connector 8, cable 4, and connector 9. The program required by the second processor 13 is loaded.

When the processor 7 completes loading the program into the RAM 12, it starts the processor 13, so the processor 13 reads the program stored in the RAM 12 and operates.

In this way, the processor 7 is connected to the other printed board unit 2.
The program required by the processor 13 is loaded by using the RAM 12 as a ROM, which stores the program, and reads the program when the processor 13 turns on the power. Is required.

In other words, in a device that uses multiple printed board units,
The types of ROMs will increase.

ROM needs to be replaced every time a program is changed, and it is usually installed using an IC socket, so increasing the number of ROMs becomes expensive and complicated to manage, increasing the cost of the device. This is because it is an invitation.

Therefore, - the programs used by the processors used in the device for boat fishing are stored together in one ROM;
The processor of the printed board unit equipped with ROM,
Programs required by the processors of other printed board units are loaded into the RAM.

The cable check circuit 10 monitors the voltage at the terminal A shown in FIG. 3(C), for example, and detects the occurrence of a connection failure in the cable 4. That is, as shown in the figure, the voltage supplied from the power source 11 to the terminal A via the resistor is applied to the circuit to which the terminal A is connected, via the connector 9, the signal line 2 of the cable 4, and the connector 8. Since it is connected to the earth via the return wire ■, the connector 8, the signal line ■ of the cable 4, and the connector 9, it is zero if there is no connection failure in the cable 4, and one side of the connector 8 or 9 is connected to the earth. If a failure such as disconnection occurs and a connection failure of the cable 4 occurs, the voltage becomes equal to the voltage supplied by the power supply +V.

Therefore, the cable check circuit 10 connects the terminal A to the power supply +
When a voltage equal to (2) is generated, a flag indicating that a connection failure of the cable 4 has occurred is set in the input register 11. When the flag is set in the input register 11, the processor 13
The driver 17 sets the interface signal set in the output register 16 to the cable 5 via the connector 18 to notify the host device 3 of the connection failure of the cable 4. Notify of occurrence.

In addition, the processor 13 connects the cable 4 to the display register 14.
Sets the status indicating that a connection failure has occurred. The status set in the display register 14 is sent to the display panel 15, and the display panel 15, which is composed of a light emitting diode or a 7-segment display,
Displays connection failure occurrence.

[Problem to be solved by the invention]

As mentioned above, conventionally, when the power is turned on, the processor 7 of the printed board unit 1 loads the program required by the processor 13 of the printed board unit 2 stored in the ROM 6 into the RAM 12. Sometimes, if a connection failure occurs in the cable 4, the program cannot be loaded into the RAM 12.

Therefore, since the processor 13 does not operate, the cable 4
It is not possible to report the occurrence of a connection failure to the host device 3,
Moreover, it cannot be displayed on the display panel 15 either.

Therefore, the host device 3 cannot grasp the details of the fault, and maintenance personnel cannot also recognize the details of the fault because the status is not displayed on the display panel 15. Therefore, there is a problem in that the restoration work takes a long time.

In view of these problems, the present invention aims to display the occurrence of a connection failure in the cable 4 on the display panel 15 regardless of the operation of the processor 13.

[Means to solve the problem]

FIG. 1 is a block diagram illustrating the invention in detail.

The storage means 20 is loaded with a program from another printed circuit board unit connected by a cable 4, and is loaded with a program from the processor 13.
reads the program loaded into the storage means 20 and operates. Then, the processor 13 sends the collected status to the display means 22 via the transfer means 21 for display.

When the detection means 19 detects a poor connection of the cable 4 via the connector 9, it sends a status signal indicating the poor cable connection to the transfer means 21. The transfer means 21 is the detection means 1
9 sends out a status signal, this status signal is directly transferred to the display means 22 and displayed.

[Effect]

By configuring as described above, even if a connection failure occurs in the cable 4 and the program is not loaded into the storage means 20 from another printed board unit and the processor 13 cannot operate, the transfer means 21 will still be able to detect the detection means 19. Since the output is directly transferred to the display means 22, the detection means 19 that detects the occurrence of a connection failure in the cable 4 can cause the display means 22 to display a status indicating the cable connection failure.

〔Example〕

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

The same reference numerals as in FIG. 3 indicate the same functions. RAM12
A program is loaded from another printed board unit via cable 4 and connector 9. The processor 13 reads the program loaded into the RAM 12 and operates, and sends the collected status to the display switching circuit 24 via the display register 14.

The display switching circuit 24 sends the status set in the display register 14 to the display panel 15 for display. Further, as described above, the processor 13 causes the driver 17 to send the status to the host device via the output register 16 via the connector 18 and the cable 5.

Similarly to the above, the cable check circuit 23 monitors the occurrence of a connection failure in the cable 4, and when a connection failure occurs in the cable 4, it sends a status indicating the occurrence of a connection failure to the display switching circuit 24.

When the display switching circuit 24 receives this status from the cable check circuit 23, it switches the circuit and sends the output of the cable check circuit 23 to the display panel 15.

Therefore, the display panel 15 displays a status indicating a connection failure of the cable 4.

〔Effect of the invention〕

As explained above, the present invention prevents a connection failure from occurring in a cable in a printed board unit that displays the status collected by a processor operated by a program loaded into RAM from another printed board unit connected by a cable. , it is possible to display a faulty cable connection even if the program is not loaded.

[Brief explanation of drawings]

FIG. 1 is a block diagram explaining the present invention in detail, FIG. 2 is a block diagram of a circuit showing an embodiment of the present invention, and FIG. 3 is a block diagram explaining an example of the prior art. In the figure, 1.2 is a printed board unit, 3 is a host device, 4.5 is a cable, 7.13 is a processor, and 6 is a ROM. 8.9.18 is a connector, 10.23 is a cable check circuit, 11 is an input register, 12 is a RAM, 14 is a display register, 15 is a display panel, 16 is an output register,
17 is a driver, 19 is a detection means, 20 is a storage means, 21 is a transfer means, 22 is a display means,
24 is a display switching circuit. (α) An example of Yaku Weifu technique Descendant explanatory flow block diagram Figure 3 (Busy no 1) ((1,) An example of Juweifu elbow E Yue Ming Tero block diagram Figure 3 (℃ no 3)

Claims (1)

[Claims] A storage means (20) into which a program is loaded from another printed board unit connected by a cable (4), and a processor (20) which reads and operates the program loaded into the storage means (20). 13), a detection means for detecting a poor connection of the cable (4) and notifying the processor (13), and a display means (22) for displaying the status collected by the processor (13). The printed board unit is provided with a transfer means (21) that directly transfers the output of the detection means (19) to the display means (22), and when a connection failure occurs in the cable (4), the detection means (19) ) causes the display means (22) to directly display a status indicating a cable connection failure.