JPS62285163A - Channel controller - Google Patents

Abstract

PURPOSE:To accept the request of low priority by making a received request in case this request is given again from a channel that produced an unprocessed request. CONSTITUTION:When the request produced by each circuit is accepted by a data processing part 50, it is checked with reference to a flip-flop group 54 and in response to channels 41-44 whether these channels 41-44 corresponding to those requests are equal to the channels related to the phenomena which are processed by the part 50. Then the requests of channels under processing are masked and the request having the highest priority among those unmasked requests is accepted. As a result, the requests having lower priorities can be accepted even in case the processes of high priorities are continuously carried out with the same channel in a data chain, etc. Thus the generating frequency of overruns can be greatly reduced.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a channel control device. In particular, receiving requests from the data transfer section, channel connection section, etc. to the microprogram control section is related to the processing stage.

〔overview〕

According to the present invention, when a request is received by a channel control device in a processing means, when an incoming request is requested again from the channel that issued the unprocessed request, the request is masked so that the request with a low priority is processed. It is made so that it can be accepted.

[Conventional technology]

FIG. 2 is a diagram illustrating a conventional channel control device having a request receiving means. Channel control device 14
controls data transfer between channels 10-13 and memory 15. For example, data between the channel 10 and the memory 15 is transferred along the channel 10 - channel connection section 16 - data transfer section 18 - memory 15 route.

Furthermore, data transfer requires various processes such as transfer start, transfer end, data chaining, and paging, and information for this purpose is managed by the data processing unit 20. Channel connection parts 16 and 17 and data transfer part 1
If such processing becomes necessary on the 1st and 19th,
The data processing unit 20 sends a request signal along with a channel number and a request code to the data processing unit 20.
request to. Among the request signals sent from the channel connection sections 16 and 17 and the data transfer sections 18 and 19 to the data processing section 20, the request with the highest priority according to a predetermined priority order is selected by the priority selection circuit 2.
1, the request is accepted by the circuit 22, and an instruction is given to the microprogram control circuit 23. Channel connection sections 16 and 17 and data transfer section 18
In this example, up to two requests can be accepted and processed from the microprogram control circuit 2 and 19 under the control of the circuit 22.
At step 3, the channel number of the request currently being processed is set in one of the channel number holding registers 24 and 25. By the way, when processing requests regarding the same channel, if the order of the processed results is out of order, a malfunction will occur in data transfer. In order to avoid this, channel number 3 related to the request signal 31 selected by the priority selection circuit 21
0 is compared with the contents of the channel number holding registers 24 and 25 by the channel number comparison circuits 26 and 27, and if the channel number 30 is the same as the contents of either of the registers 24 and 25, the NOR gate 28 and the AND gate 29 are compared.
The request signal 31 is masked to prevent this request from being rejected. When processing for a certain channel is completed and the microprogram control circuit 23 notifies the request reception circuit 22 of this fact, the request reception circuit 22 selects the channel for which processing has been completed among the channel number holding registers 24 and 25. Reset the register that holds the number. This makes it possible to accept requests regarding channels for which processing has been completed. In this way, overtaking of requests related to the same channel is avoided.

[Problem that the invention seeks to solve]

However, if the highest priority request is not accepted because the channel for that request matches the channel currently being processed, lower priority requests will have to wait longer and overrun. It's easy to do.

SUMMARY OF THE INVENTION The present invention aims to eliminate such drawbacks and to provide a channel control device that can accept low priority requests and reduce the frequency of overruns.

[Means for solving problems]

The present invention is arranged between a plurality of channels and a memory, and receives a plurality of request signals among request signals related to data transfer from the channel to the memory according to priorities assigned in advance to the request signals. In the channel control device, the above-mentioned channel control device is provided with reception means (51, 52) and control means (53) for controlling the transfer of the data based on the processing result of the request signal received by the reception means. storage means (54) for storing a signal identifying a channel related to a request signal received by the lighting means until the request signal is processed by the control means; and a storage means (54) corresponding to the signal stored in the storage means. masking means (71 to 78) for prohibiting output of a newly arrived request signal from a channel to the receiving means; the storing means is a flip-flop provided corresponding to the channel; The masking means is configured to maintain a predetermined level until the request signal related to data transfer from the channel is processed by the means, and the masking means is held in the flip-flop corresponding to the channel related to the newly arrived request signal. The present invention is characterized by comprising a detection means for detecting whether or not the level of the current level is the predetermined level.

[For production]

The channel control device receives and processes a plurality of request signals from among request signals having mutually different priorities generated from a plurality of circuits. A flip-flop indicating whether a request is being accepted for each channel masks requests related to channels for which requests are being processed. Among the requests from each unmasked circuit, the request with the highest priority is accepted.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG.

This embodiment device has channel connections 46 and 47 to which channels 41 and 42 and channels 43 and 44 are connected, respectively, and data transfer units 48 and 49 having interfaces with channel connections 46 and 47, respectively. parts 46 and 47 and data transfer part 4
The data processing section 50 receives requests from the channel connection sections 46 and 47 and the data transfer sections 48 and 49, respectively. AND gates 75 to 78 and request reception circuit S
2, and a priority selection circuit 51 which selects the request with the highest priority from the valid outputs 59 to 62 of the AND gates 75 to 78 according to a predetermined priority order and sends the request reception to the circuit 52. Then, the request is accepted by the microprogram control circuit 53 that processes the request accepted by the circuit 52, and only the flip-flop corresponding to the channel being processed by the microprogram control circuit 53 is set to rOJ, and the other flip-flops are set to rOJ. is a flip-flop group 54 corresponding to each channel set to "1", and a flip-flop selection circuit 71 that selects flip-flops corresponding to channel numbers 63 to 66 from the flip-flop group 54, respectively.
~74. In the figure, numerals 63 to 66 indicate channel numbers associated with request signals 55 to 58, respectively, and numerals 67 to 70 indicate request signals 55 to 58, respectively.
The reference numeral 79 indicates a control signal for the flip-flop group 54.

Now, requests generated on channels 41 and 42 enter channel control device 45 via channel connection section 46, and requests generated on channels 43 and 44 enter channel control device 45 via channel connection section 47. Channel connection units 46 and 47 issue requests to data transfer units 48 and 49 or data processing unit 50 depending on the type of request from the channel. In addition, the data transfer units 48 and 49 also send a request signal along with a channel number and a request code to the data processing unit 50 in order to import information necessary for processing such as data chaining and paging. We expect that processing.

In this way, requests are sent to the data processing unit 50 from a plurality of circuits. On the other hand, the maximum number of events that can be processed by the data processing unit 50 at one time is determined, and if there is still room for the number of events being processed, the request is accepted by the circuit 50.
2, the request can be accepted, and the flip-flop corresponding to the channel number associated with the request in the flip-flop group 54 is set to rOJ, and the request processing is instructed to the microprogram control circuit 53. When accepting a request, the microprogram control circuit 53 performs necessary processing depending on the type of request accepted by the circuit 52, and when all processing related to one request is completed, the microprogram control circuit 53 notifies the circuit 52 when accepting the request. The flip-flop corresponding to the channel whose processing has been completed in the flip-flop knob group 54 is set to rlJ, and the processing of one event is completed. If there are still events to be processed, they are processed, and if there are no events to be processed, the process waits for a new request to be accepted by the request acceptance circuit 52.

However, when two requests are received from the same channel and processed by the microprogram control circuit 53, it is uncertain which process will be completed first. On the other hand, flip-flop selection circuits 71 to 7
In step 4, a flip-flop corresponding to the channel of the event to be processed is selected from the flip-flop group 54, and if the content of the selected flip-flop is "0", the request is masked by AND gates 75 to 78. and prevents it from reaching the priority selection circuit 51. This prevents processing from being overtaken by the same channel, and even when high-priority requests regarding the same channel occur continuously in a data chain, etc., the processing related to the channel of the high-priority request is executed by the microprogram. If the request is being executed by the control circuit 53, a request with a lower priority can be selected by the priority selection circuit 51.

〔Effect of the invention〕

As explained above, when the data processing unit receives a request generated in each circuit, the present invention checks whether the channel corresponding to this request is a channel related to the event being processed by the data processing unit. The response checks the flip-flop group, masks the request related to the channel being processed, and accepts the request with the highest priority among the requests that were not masked, so high priority processing of the same channel in data chain etc. Even if requests are being made continuously, requests with a lower priority can be accepted, which has the effect of significantly reducing the frequency of overruns.

[Brief explanation of drawings]

FIG. 1 is a block configuration diagram showing the configuration of an apparatus according to an embodiment of the present invention. FIG. 2 is a block configuration diagram showing the configuration of a conventional device. 10~13.41~44...channel, 14.45・
...Channel control device, 15...Memory, 16.17
．． 46.47...Channel connection part, 18.19.48
．． 49...Data transfer unit, 20.50...Data processing unit, 21.51...Priority selection circuit, 22.52...
・Request reception circuit, 23.53...Microprogram control circuit, 24.25...Channel number holding register, 26.27...Channel number comparison circuit,
28... Noah gate, 29.75-78... AND gate, 30.63-66... Channel number, 31.
55-62...Request signal, 54...Flip-flop group, 67-70...Request code, 71
~74...Flip-flop selection circuit, 79...Control signal.

Claims (1)

[Claims] (1) Acceptance of receiving multiple request signals according to the priority assigned in advance to the request signals among the request signals interposed between multiple channels and the memory and related to data transfer from this channel to this memory. means (51, 52); and a control means (53) for controlling the transfer of the data based on the processing result of the request signal received by the reception means, storage means (54) for storing a signal identifying a channel related to the request signal until the request signal is processed by the control means; and a request newly arriving from a channel corresponding to the signal stored in the storage means. mask means (71 to 78) for prohibiting the output of a signal to the receiving means; the storage means is a flip-flop provided corresponding to a channel; and the control means receives a request related to data transfer from the channel. The masking means maintains a predetermined level until the signal is processed, and the mask means maintains the level held in the flip-flop corresponding to the channel related to the newly arrived request signal at the predetermined level. A channel control device characterized by comprising a detection means for detecting whether or not there is a channel.