JPS60142425A - Scanning control system - Google Patents

Abstract

PURPOSE:To reduce time loss by discriminating whether data sent to the device side is a long mode or a short mode and processing the data on the device side in a scanning control system. CONSTITUTION:When data is sent from a service processor, a mode detecting circuit 12 decodes a scan address signal to identify whether the sent scan data are in the long mode or short mode on the divece side. In case of the long mode, a bit count 32 signal is received through an AND gate 6 and an FF0 is set by the output of the gate 6 to output a long scan end signal. In case of the short mode, a bit count 8 signal is received through an AND gate 7 and an FF10 is set by the output of the gate 7 to output a short scan end signal.

Description

Detailed Description of the Invention α) Technical Field of the Invention The present invention relates to scan control between a service processor and other devices in an information processing system.

(2) Prior art and problems FIG. 1 is a diagram showing a connection system between a service processor and other devices. ~2U is the device,
3 to 5 are signal lines.

In FIG. 1, the service processor 1 includes each device 21 to
2 degrees, information is transferred bit-serial using signal lines 3 to 5, and these devices are scan-controlled.

The signal line 3 transfers a device number signal (parallel signal), the signal line 4 transfers a scan address signal (parallel signal), and the signal line 5 transfers a scan data signal (serial signal). Each device 2, ~
In the case of 2 units, the signal line 4.5 is connected only when the machine number signal on the signal line 3 matches the own machine number.

Figure 2 is a diagram showing the scan control registers, each with a different scan address. Two of the many registers are indicated by ``A'', the arrow indicates the shift direction, and ``IN'' indicates the shift direction. OUT stands for the scan-in side, OUT stands for the scan-out side, D stands for the data section, LINE stands for the address section, C stands for the control section, and N stands for the unused section.
The number ~31 is the bit position 0 Conventionally, in this type of scan control, the device side starts processing after scanning one word (32 bits) regardless of the data length, so the control When the information in part C is shifted rightward on the scan control register on the receiving side and the data at bit 31 in Figure 2 reaches the bit 7 position, the control content is determined on the device side and processing is started for the first time. It had started.

Therefore, there is a drawback that there is a large time loss from the time the control section information is transferred until it is decoded on the device side.

(3) Purpose of the Invention In view of the above-mentioned conventional drawbacks, the present invention provides a method that can reduce time loss by detecting information in a control unit related to scan control early and starting full processing. The entire purpose is to provide

(4) Structure and object of the invention According to the present invention, the effective number of bytes of information to be transferred in a device controlled bit-serially in units of multiple bytes by a service processor is as described in the claims. This is achieved by a scan control method characterized in that processing is started based on information about the number of bytes in the scan address from the service processor.

(5) Embodiment of the Invention FIG. 3 is a circuit diagram of an identification circuit used in an embodiment of the present invention, and shows a circuit for detecting all memory write signals from a control section for scan control data from a service processor. 6 to 8 are AND gates, 9 to 11 are flip-flops, and 12 is a mode detection circuit.0 In Figure 3, when data is sent from the service processor, the scan address is Signal (1st
The address signal sent via signal line 4 in the figure) is decoded by the all mode detection circuit 12 to determine whether the scan data being sent is long mode (32 bits) or short mode (8 bits).
It identifies whether it is a bit or not and controls the gate provided for each. For example, when data in the data field (D) and address field (A) are sent to the upper register shown in Figure 2, a long mode signal is detected from the scan address that specifies the register, and the AND gate 6
The gate 6 receives the bit count 32 signal by making use of the
The output flip-flop 9 is set to output all long scan end signals. Furthermore, when receiving the control unit (C)k to the lower register shown in Figure 2, the short mode is detected from the scan address, and the bit count 8 signal is received using the AND gate 7 in Figure 3. The flip-flop 10 is set by the output of the gate 7, and a short scan end signal is output. The short scan end signal is input to the AND gate 8, and the AND gate 8 inputs the scan address and bit 31 (
The flip-flop 11 is set under the conditions of the bit representing memory write, and a memory write signal is output.

(6) Effects of the Invention According to the method of the present invention, when the service processor scans each device, the device side determines whether the data sent is in long mode or short mode based on the scan address information. Since it identifies and processes all
This has the advantage of less time loss and efficient control.

[Brief explanation of the drawing]

Figure 1 shows the connection system between the service processor and other devices, Figure 2 shows the scan control register, and Figure 3 shows the connection system between the service processor and other devices.
The figure is a circuit diagram of an identification circuit used in one embodiment of the present invention.

Claims (1)

[Claims] In a device that is controlled by a service processor bit-serially in units of multiple bytes, the number of effective bytes of information to be transferred is identified by a scan address signal from the service processor, and information on the number of bytes is identified. A scan control method characterized in that immediately after receiving the information, all processing is started based on the information or the information based on the bits included in the information.