JPS58111546A - Communication controller - Google Patents

Abstract

PURPOSE:To provide a margin for the limit of processing time of a character processing section and to mitigate the design condition of the character processing section, by taking transmission and reception buffers as one and two characters, respectively and providing a circuit masking a reception processing request signal. CONSTITUTION:A character decomposing section 2b reads data for one character's share from a transmission register 4, transmits a serial data for one character's share to a line 1b and also a transmission character processing request 10 to a character processing section 3, which transmits the next data to the transmission buffer 4. The serial data of the section 2 from the line 1a is reconstituted into the parallel data and transferred to a reception register 5, and when a reception register 6 is vacant, a reception character processing request 12 is given and transferred to the register 6. The request 12 is masked at a mask circuit 7 for a prescribed time before the generation of the request 10.

Description

[Detailed description of the invention] The present invention relates to a communication control device.

In an online information processing system, the basic function of the communication control device, which exists between the central processing unit system and the communication line and controls the transmission and reception of data between the central processing unit and a wide variety of terminal devices located in remote locations, is to Disassembly and Assembly 1 Processes include connection control and status monitoring of communication lines, G49 control, and transmission control according to predetermined procedures. In general, 1. This type of communication control device has a buffering function in order to reduce program interruptions to the central control unit and improve processing capacity, and assembles data into at least one character, and transfers data between it and the central processing unit. Control giving and receiving.

A conventional communication control device includes a character disassembly and assembling unit that disassembles and assembles transmitted and received data (serial data) to/from a communication line in units of t-1 characters, and a character disassembly and assembly unit that disassembles and assembles data sent and received (serial data) to/from a communication line in character units. It has a character processing unit that transmits and receives (parallel data) and performs processing such as control according to transmission control specifications, and the transmitting side and receiving side of the character disassembly and assembly unit,
On the side, there is a transmitting character buffer and a receiving character buffer for holding one character's worth of parallel data (usually 8 bits) from/to the character processing section. When transmitting serial data from this communication control device to a communication line, the character disassembly/assembly unit Fi decomposes data for one character into serial data and sends it to the communication line, and when this transmission is completely completed, the next sending data is sent to the transmission character buffer. (At this time, the transmission character buffer becomes 1 free space.) This data transmission continues, and 2
Sends a transmission character processing request to the character processing section. The character processing section processes this transmission character processing request and further transfers the next transmission character to the transmission character buffer.

Since characters are sent to the communication M1 at a rate of one character during a fixed time T, transmission character processing requests are sent at intervals of this fixed time T. On the other hand, when serial data is received from a communication line, the character disassembly and assembling section assembles the received clear data into parallel data, transfers it to the reception character buffer, and sends a reception character processing request to the character processing section. The character processing section reads and processes the parallel data tg held in the received character buffer. This makes the receive xelector buffer "empty". Since character processing requests are generated at intervals of the predetermined time '1', the character processing section receives all of these requests once and performs processing 7.

As is clear from the above explanation, if the 5 character processing unit does not finish processing one transmission character processing request or one reception character processing request within the above-mentioned time T, an underground/overrun will occur. do.

That is, on the sending side, as soon as the transmission character buffer becomes empty, the next transmission character processing request is generated, and within a certain time T, the transmission character buffer becomes empty. ! It is necessary for ζ data to be set to v'', but when this is not possible and @empty remains at 1, a 4 underrun occurs, and on the other hand, on the receiving side, the receive character buffer is 0.
Since the next received character processing request occurs before the space is filled, an overrun state occurs.

The above sending character processing request and receiving character processing request are.

As mentioned above, 1,000n-t'n occurs at one-character intervals, that is, at intervals of a certain time T, but since the timing of both occurrences is independent of each other, a case like the one shown in Figure 1 appears. . FIG. 1 is a time chart showing an example of the generation timing of a general transmission character processing request and a reception character processing request. The figure shows a case where received character processing requests are generated sequentially at intervals of a fixed time T, and transmission character processing requests are delayed by a time Δt than the received character processing requests and are issued sequentially at intervals of the fixed time T. show.

In this case, it is clear that if the conventional communication control device does not process one transmission character processing request and one reception character processing request during the time '1'+Δt, an underrun or overrun state will occur. The time required for character processing in the character processing unit differs for each character depending on the conditions when performing transmission control procedure processing and character storage processing, but some characters require a particularly long processing time. There is something. Therefore, a character processing section capable of processing both of the above character processing requests during the time T+Δt has a disadvantage in that it is extremely expensive due to severe design conditions.

SUMMARY OF THE INVENTION An object of the present invention is to provide a communication control device v1k in which the processing time limit of the character processing section is relaxed and the design conditions of the character processing section are relaxed.

The "communication 6J1" control device according to the present invention includes a character disassembly and assembling section that disassembles and assembles all data sent and received to and from one communication line into character units, and a character disassembly and assembling section that disassembles and assembles all data transmitted and received to and from one communication line in character units, and a character disassembly and assembly section that disassembles and assembles all data transmitted and received to and from one communication line in character units. In a communication control device configured to include a character processing unit that processes data, a transmission character buffer for one character, first and second reception character buffers for each one character, and the character decomposition A mask circuit that cuts off the signal for sending out a received character processing request to the character processing section between the n sections determined by the mask instruction from the assembly section for the number of characters! The Is assembling section is located between the character processing section and the character processing section.

Next, the present invention will be explained with reference to FIGS. 2 and 3.

FIG. 2 is a block diagram showing an embodiment of the communication control device of the present invention. This embodiment includes a character decomposition unit 2b that decomposes parallel data in units of characters into serial data and transmits it to the transmitting side communication line *ib, and a receiving n communication line 1. a character disassembly and assembling section 2, which assembles the serial data received from a into parallel data character by character;
A character processing unit 3 is provided which processes the parallel data in units of characters in response to a transmission character processing request 10 or a reception character processing request 11, and the character processing unit 3 is provided between the character processing unit 3 and the character decomposition unit 2b. A transmitting register 4 that holds parallel data for one character from the character assembling section 2a is connected between the character assembling section 2a and the character processing section 3. A reception register A5 and a reception register l'6 holding parallel data are connected in series.

Roughly, between the character assembly section 2a and the character processing section 3, a mask instruction 11 from the character disassembly section 2b prohibits sending of the received character processing request 12 to the character processing section 3 for a predetermined period. It is configured by connecting a mask circuit 7 to

Next, the operation of this embodiment will be explained. Character decomposition unit 2b
decomposes one character's worth of parallel data into serial data and sends it to the sending side communication line 1b, and when this transmission is dead, reads the next sending data from the sending register 4 (at this time, the sending register 41 character unit) 7. Sequentially transmit the real data to the transmission side communication circuit #1j. Also, the character decomposition unit 2b
is given to the mask circuit 7 at a predetermined time before the transmission character processing request is generated. In accordance with this instruction, the mask circuit 7 processes the character processing unit 3 of the received character processing request 12.
Mask interrupts to. On the other hand, the character assembling unit 2a receives serial data from the receiving side communication circuit @la and assembles it into parallel data, character data for one character C) 11
is transferred to the reception register A5, and the reception register B6 is 6 free. Then, the content of the reception register A5 (the character data U) is transferred to the reception register B6, and the received character processing request 12 is sent. However, depending on the timing of occurrence, the interrupt to the p character processing section 3 may be masked by the mask circuit 7 according to the mask instruction 11.
Ru. When the character assembling unit 2a receives character data CH for the next character, it transfers it to the reception register A5 which is now "empty". When the above-mentioned mask is released, an interrupt of a received character processing request 12 is made, and the contents of the reception register B6 (the character data CH,) are read into the character processing section 3, and reception processing is performed. Also, receive register A5
The contents held in (the character data CH,)
is transferred to the reception register B6 which is now "empty". Receiving side communication time 1i! Character data CH3 and subsequent character data for the next character of the serial data from la are similarly transferred sequentially to reception register A5 - reception register B6 - character processing section 3, where n reception processing is performed.

Next, FIG. 3 is a time chart showing an example of the relationship between the interrupt mask time of the received character processing request and the processing limit timing in the character processing section in FIG. 2. In the figure, the relationship between the generation of received character processing requests and transmitted character processing requests is the same as that shown in FIG. That is, the received character processing request lR□ occurs at time t01c, and thereafter, the received character processing request lR211 is made at intervals of a certain time Il+.
01~ occur sequentially. In addition, the sending character processing request 81 is a request for processing received characters, rt delayed by time Δt from □,
It is assumed that the transmission character processing requests ``821'', ``83'', etc. occur in sequence at fc time t1, and thereafter at intervals of the predetermined time T. Since the received character processing request lR□ occurs at the time 10 within the received character processing request interrupt mask time, it cannot immediately enter the character processing unit 3, and the time t1 when the mask time Tm has elapsed. An interrupt fee is paid at (indicated by lR'□). Received character processing request IR
The same applies to 2.lR31~.

Note that the interrupt reception character processing request IRI l~ is the same time point tl + time Tm as the transmission character processing request '81'~ can be set to a desired value by the inhibit time signal from the character decomposition unit. It's ringing.

As explained above, the communication control ife! of this embodiment! Since t is equipped with a transmission register for one character and a reception register for two characters, the single character processing unit 3 sends a transmission character processing request "81".
tThe period from the time t1 when the next transmission character processing request ``si'' occurs, that is, from the time tl when the clock is released until the reception character processing request IR3 occurs, that is, the difference between the time t3 and the time t1. It is good to process n within the time 2T-Δ.Here, if Δt=T/2, n means that one character processing unit 3
is 1 hour for one received character processing request 2T-Δt=
This means that it is only necessary to process within 1.5T, and there is a margin in the processing limit timing compared to the conventional method. Further, if the time Δt is longer than the mask time Tm, the received character processing request "R1l IR21" R31~ is masked.
Therefore, the received character processing requests ``R1'' and ``R211R31~ will be processed before the transmitted character processing requests ``81t'' and ``8□11931~. Therefore, n occurs within time Δt+T from the time when the received character processing request IR1 is generated.

It is sufficient to process the received character processing request □ and the transmitted character processing request 18□. In other words, it is only necessary to process one received character processing request and one transmitted character processing request X within the above-mentioned time Δt+1. Here, the time '1m=T/2 and Tn
rJ: Before Ae4 Δt + T〉i, s T.

There is more margin in the processing limit timing than in the conventional system.

Note that this example does not limit the present invention.

In other words, the transmitting register and receiving register may be included in the AI manual disassembly and assembly section to form a groove, or one full-duplex line (one @ transmitting and receiving communication line) is shown, but multiple full-duplex lines may be used. Needless to say, in the case of multiple lines, it is sufficient to provide the required number of communication control devices of this embodiment.

As is clear from the above explanation, by using the communication control device of the present invention, the design conditions of the character processing section can be made extremely vague by giving a margin to the character processing time +7. The effect is that even if there are characters that require a particularly long processing time, it is easier to design for them, and the economy is significantly improved.

[Brief explanation of the drawing]

FIG. 1 is a time chart showing an example of the generation timing of a general transmission character processing request and a reception character processing request, gXZ is a block diagram showing an embodiment of the communication control device of the present invention, and FIG. 12 is a time chart showing an example of the relationship between the interrupt mask time of a received character processing request and the processing limit timing in a character processing section in FIG. 1aνlb-゛・°・・・Communication line, 2...Character disassembly and assembly section, 3...Character processing section, 4...
・Transmission register, 5゜6...Reception register A,
B, 7. Old mask circuit, 10... Transmission character processing request, 11... Mask instruction. 12... Received character processing request. 1st cruel 41st 2nd closed h Figure 3 @1 t2 t3

Claims (1)

[Claims] A character disassembly and assembling unit that disassembles and assembles data to be transmitted and received over a communication line into character units, and a character processing unit that processes data transmitted and received in character units to and from the communication line via the character disassembly and assembly unit. In the communication control device consisting of n, there is a transmission character buffer for one character, and two
a first and second reception character buffer for L1 characters, and a mask circuit that disconnects a read signal for sending a reception character processing request to the character processing section for a period of n determined by a mask instruction from the character disassembly and assembly section. A communication control device characterized in that the communication control device is provided between the character disassembly and assembly section group and the character processing section.