JPH01209557A - Contention processing system for bus application request - Google Patents

Abstract

PURPOSE:To ensure a smooth data processing system by applying rotary priority processing to a bus application request received from a general input/output device and then applying fixed priority processing to the bus application request of the highest priority order received from a specific input/output device. CONSTITUTION:The bus application requests received from the general input/ output devices 21-2n undergo the rotary priority processing through a rotary priority processing circuit 4. Then these processed requests undergo the fixed priority processing via a fixed priority processing circuit 3 for contention with the bus application request of the highest priority order received from a specific input/output device 20. The bus application request is informed to a control processor 1 through the fixed priority processing. Thus the bus application request received from the device 20 is processed with the highest priority order. While the requests received from those devices 21-2n have the priority orders lower than that of the device 20 and are evenly processed. As a result, data can be smoothly processed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for adjusting and processing the competitive relationship between bus usage requests from each input/output device, and particularly relates to a method for adjusting and processing the competing relationship of bus usage requests from each input/output device, and in particular, This invention relates to a bus use request competition processing method in which requests are processed with priority.

[Conventional technology]

Until now, as described in Japanese Patent Publication No. 5B-51294, priority has not been assigned in advance to the processing of the bus use request signal to the bus control circuit, and therefore, the bus use request signal is It is now processed evenly.

[Problem to be solved by the invention]

Up to now, each bus request that occurs independently is processed equally, but there is also rotational priority processing in which the priority is sequentially variable, and bus usage request reception. The order is fixed and next fixed priority processing is considered. However, when a control processing unit accommodates multiple input/output devices via a common bus, fixed priority processing is adopted to preferentially process bus usage requests from specific input/output devices. However, there is a problem in that the number of times a process is executed in response to a bus use request from an input/output device with the lowest priority is extremely reduced.

An object of the present invention is to process bus usage requests from a specific input/output device with the highest priority, while processing bus usage requests from other input/output devices with equal probability. We provide a complete set of methods for dealing with usage fees and competition.

[Elaborate means to solve problems]

The purpose of the above is that bus usage requests from other general input/output devices are processed with rotational priority, and then bus usage requests from specific input/output devices with the highest order priority are processed first. It is achieved by being

[Effect]

Bus usage requests from t% of general input/output devices are first processed with rotational priority, and the bus usage requests as a result of this processing are then processed by specific input/output devices with higher priority bus usage! ! Conflict processing using Mukaidadari processing is performed between the two. Assuming that notification of a bus use request to the control processing unit is performed by fixed priority processing,
Bus usage requests from specific input/output devices are processed with top priority - 1, for bus service from many input/output devices in the pond! ! The bus usage requests from Kabutsuji-specific input/output devices are given a lower priority and are processed evenly.

(Example) The present invention will be explained below with reference to the accompanying drawings.

The figure shows seven examples of processing systems according to the present invention. As shown in the figure, input/output devices 20 to 20 are peripheral devices.
29 is accommodated in the control processing device 1 via the common bus 6, but the input/output devices 20-2? When a request to use the common bus 6 is generated for each of the L devices, the bus request signals 70 to 79 from each of the input/output devices 20 to 25 are processed in a predetermined manner by the competition processing section 5.

That is, when a request to use the common bus 6 is generated in the input/output device 2 (l), the fixed priority processing circuit 5 in the competition processing section 5 is notified of the bus request signal 7o.

However, in the fixed priority processing circuit 5, the bus acknowledge signal 891 indicating that any one of the input/output devices 71 to 7n is in the operation of turning out people is not sent to the rotation priority processing circuit 4. After confirming that, the bus request signal 7o is given priority over the bus request signal 7tL+z from the one-rotation/priority processing circuit 4, and the bus request signal 79+2 is sent to the control processing device 1. There is. As a result, the control processing device 1 releases the common bus 6 and then sends a bus acknowledge signal 8n+x to the fixed priority processing circuit 3.

The fixed priority processing circuit 3 also sends out the input/output device 20.
Permission to use the common bus 6 is notified by sending a bus acknowledge signal 8o to the terminal. Also, if it is solid.

When the bus acknowledge signal 891 is sent from the constant priority processing circuit 3 to the rotation priority processing circuit 4, the bus request signal from the input/output device 2+1 is sent after the sending of the bus acknowledge signal 8+1 is completed. 7o is attached, and the common bus 6 to the input/output device 20 and release processing are performed. Upon completion of the input/output operation, the bus request signal 7o is sent.

From this point, the sending of the bus acknowledge signal 8 series is also stopped.

Furthermore, when the bus request signal 7° is not generated in the input/output device 20, the input/output devices 21-2? Any one of L
When more than one bus request signal is generated, these bus request signals are subjected to competing processing in the rotation priority processing circuit 4.

Since the priority order of the bus request signal 71 to 7% in the rotation priority processing circuit 4 is sequentially rotated, the input/output device 2
As a result, equal priority is given to 1-2%. When the rotation priority processing circuit 4 accepts one or more of the bus request signals 71 to 7%, it accepts the one with the highest priority, and sends the bus request signal 7n+1 to the fixed priority processing circuit 3. This is what will be sent. The fixed priority processing circuit 3 also sends a bus request signal 7n+2 to the control processing device 1, so that the control processing device 1 releases the common bus 6 and then sends the bus request signal 7n+2 to the rotation priority processing circuit 4 via the fixed priority processing circuit 5. In response to this, a bus acknowledge signal of 8% + 1° is sent. As a result, the rotation priority processing circuit 4 sends a bus acknowledge signal to one of the input/output devices 21 to 22L to which the bus request signal has been accepted, thereby notifying that device of permission to use the common bus 6. This is what is meant to be done.

As mentioned above, bus request signals from specific input/output devices are processed preferentially compared to others; however, since bus request signals from other input/output devices are processed equally, By setting a high-performance input/output device as a specific input/output device, data processing can be performed smoothly.

〔Effect of the invention〕

As explained above, according to the present invention, bus usage requests from specific input/output devices are processed with top priority, while bus usage requests from other general input/output devices are processed equally. There is an effect like this.

[Brief explanation of the drawing]

The figure is a diagram showing an example of a processing system according to the present invention. 1... Control processing device, 2o~2%... Input/output device. 3...Fixed priority processing circuit, 4...Rotation priority processing circuit, 5...Conflict processing unit, 6...Common bus.

Claims (1)

[Claims] 1. A bus usage request competition processing method in a processing system in which multiple input/output devices are housed in a control processing unit via a common bus, in which bus usage requests from each general input/output device are given equal priority. All bus usage requests from each input/output device are processed with rotational priority, and fixed priority processing is performed with the highest priority bus usage request from a specific input/output device, so that bus usage requests from each input/output device are sent to the control processing unit. A bus use request conflict handling method characterized by notification.