JPS62260453A - Digital interface control system for communication control processor - Google Patents

Abstract

PURPOSE:To allow a communication control program to control a digital interface by making each signal of a signal bit channel similar to each signal of a MODEM interface when a digital line is accomodated in a communication control processor. CONSTITUTION:Character assembly/dessembly control parts 3-1 and 3-2 assemble serial data channels from a transmission frame assembly/dessembly control part 6 to character data, hand it in a processing part 2, or conversely dessemble character data from the processing part 2 to serial data and transfer it to the transmission frame assembly/dessembly control part 6. A signal bit channel control part 4-1 supervises and controls the state of a signal bit channel on a signal line 11. A MODEM interface pseudo circuit 7 makes each signal of the signal bit channel similar to each signal of the MODEM interface. Thus the way that the communication control program controls the character assembly/dessembly control part 3-1 and the signal bit channel control part 4-1 is equivalent to the case when a conventional MODEM interface is accomodated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a digital interface control method in a communication control processing device accommodating a digital line.

[Conventional technology]

Conventionally, when controlling a modem interface accommodating a public communication line or the like in a communication control processing device, it has been common to adopt a configuration as shown in FIG. In FIG. 4, 1 is a line control unit (LC) that directly accommodates the modem interface 5, and 2 is a processing unit (PU) on which a communication control program runs and controls the line control unit 1. The line control unit 1 includes a character assembly and disassembly control unit 3 that assembles serial reception data RD into characters or decomposes the characters into serial data to generate transmission data SD, and a character assembly and disassembly control unit 3 that performs modem initialization, carrier control, and line abnormality. It consists of a signal line control section 4 that controls or monitors the modem interface signal line R5-CD for detection.

Modem initialization, carrier control, and line abnormality detection are performed in 1
This is done as follows under the control of the communication control program.

■ Modem initialization Turn on ER (Data Terminal Ready), instruct the modem to connect the line, and receive and confirm the DR (Data Set Ready) response from the modem.

- In the case of carrier control data transmission, turn on R8 (transmission request), instruct the modem to transmit the carrier, and check for a response of C3 (transmission possible) from the modem. In the case of data reception, the other party's carrier is confirmed by CD (carrier detection). After performing this carrier control, the communication control program controls the transmission and reception of data respectively. 6. Line Abnormality Detection By monitoring disconnection of C5/'CD, a modem or line failure is detected.

[Problem that the invention seeks to solve]

As described above, in the communication control processing device that accommodates the modem interface, the communication control program is transmitted through the modem interface signal lines R8, cs, and ER.

It controls the DR and CD, initializes the modem, controls the carrier, sends and receives data, and detects line abnormalities.

On the other hand, in digital lines, DSU, which corresponds to a modem,
Since the line including the digital service unit (digital service unit) is always connected, the E
There are no signals corresponding to R and DR, and since carriers are not used, there are also no signals corresponding to RS, C8 for carrier transmission control, and CD for carrier reception monitoring.
Therefore.

When accommodating a digital line in a communication control processing device, a communication control program created on the premise of a conventional modem interface signal line cannot be used as is for controlling the digital line.

An object of the present invention is to enable, when accommodating a digital line of a communication control processing device, control of the digital line without changing an existing communication control program created on the premise of a modem interface signal line.

[Means for solving problems]

The present invention provides a modem interface pseudo-circuit in the part that controls the signal bit channel of the single-line control unit, and simulates each signal of the signal bit channel in the digital line to each signal of the modem interface, so that it can be seen from the communication control program. This makes digital lines equivalent to existing modem interfaces.

[For production]

A serial bit string flowing through a digital line is generally
As shown in the figure, the transmission frame is repeated in units of (n+1) bits. By rowing.

The n bits indicate data channel 1 for transmitting and receiving data with the other terminal. The remaining bit (the bit indicated by an x) is repeated for each transmission frame, and each bit position is the transmission frame synchronization bit (F), the data channel 2 (D) that controls connection with the network, the line, etc. Network failure status display bits (A□~Ai), communication status display bit (S
ty 32). A-A is "#l11" when abnormality occurs.
．． , 1: Always 14011, Sl, S, is "1" during communication, and is "O'" during non-communication. This A1-A
1 and S, , S2 are called signal bit channels.

In the signal bit channel control unit of the line control unit in this communication control processing device, initialization of the modem and abnormality detection of the carrier control 9 line are realized in the following manner using a modem interface pseudo-circuit.

■ Modem initialization For digital lines, the digital service unit (D
ER regarding modem initialization because the line is always connected, including S tJ).

This is equivalent to a state in which the DR double signal is always on. Therefore, by creating a pseudo ER, turning on from the communication control program,
Enables off control and displays the ER instruction status with the DR read instruction.

(2) In a carrier control digital line, there is no carrier, but there is an indicator bit (S, s2) in the signal bit channel that indicates to the network or other terminal that communication is in progress. On the other hand, the R5 signal related to modem carrier control instructs the start of data transmission. Therefore, turning on R8 and turning on 81 bits is equivalent, so we create a pseudo R3, send out 81 bits with RS on control at the time of transmission, and turn on C8.
When the read instruction is issued, the instruction status of R5 is displayed. In the case of reception, 82-bit reception is made directly compatible with CD.

■ Line abnormality detection The normality of a digital line is guaranteed if all signals in the signal bit channel, including 82 bits, are normal. Since this is equivalent to the CD coverage guarantee range of the modem interface, if any bit in the signal bit channel becomes abnormal, a CD off indication is made.

〔Example〕

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

FIG. 1 is a block diagram of an embodiment of a communication control processing device of the present invention. In FIG. 1, 1 is a line control unit (LC) that accommodates a digital line 8, and 2 is a processing unit (PU) that controls the line control unit 1 using a communication control program.

The line control unit 1 is a character assembly and disassembly control unit 3-1.3-
2. Consisting of a signal bit channel control section 4-1 and a transmission frame assembly/disassembly control section 6, the signal bit channel control section 4
-1 includes a modem interface pseudo-circuit 7. 1
2 is a signal line between the line control section 1 and the processing section 2, and is composed of an address bus 12-1, a data bus 12-2, and a read/write clock 12-3.

The transmission frame assembly and disassembly control unit 6 transfers the received transmission frame shown in FIG. 3 from the digital line 8 to the data channel 1.
, into a data channel 2 and a signal bit channel,
They are transferred as serial signals to the character assembly/disassembly control section 3-1, 3-2 and the signal bit channel control section 4-1 via the signal lines 9 and 10°11, respectively, or conversely, the character assembly/disassembly control section 3-1. 1.3-2, data channel 1, data channel 2, . The signal bit channels are assembled into the transmit transmission frame of FIG. 3 and transmitted to the cidigital line 8. The character assembly and disassembly control units 3-1 and 3-2 respectively convert the serial data channels from the transmission frame assembly and disassembly control unit 6 into character and
The 6-signal bit channel control unit 4-1 assembles data into N processing unit 2, or conversely disassembles the character data from the processing unit 2 into serial data and transfers it to the transmission frame assembly and disassembly control unit 6. While monitoring and controlling the status of the signal bit channel on line 11, the modem interface pseudo circuit 7 simulates each signal of the signal bit channel to each signal of the modem interface.

FIG. 2 shows a detailed diagram of the signal bit channel control section 4-1 including the modem interface pseudo-circuit 7 of FIG.
3 is a decoder connected to the address bus 12-1 and decodes the address signal from the processing section 2; 14 and 15 are latches connected to the data bus 12-2 and holding the ER and R8 signals from the processing section 2, respectively. , 16 outputs the output of the latch 14 to the data bus 12-2 as a DR signal.
State buffer 17 connects the output from latch 15 to C8
A three-state buffer outputs a signal to the data bus 12-2, and 18 is a gate that performs the OR of each bit of the signal bit channel on the signal line 11.

A 3-state buffer 19 outputs the output from the gate 18 as a CD signal to the data bus 12-2.

20 is a gate for timing the latch 14;
1 is a gate for controlling the output state of the buffer 16;
22 is a gate for timing the latch 15;
3 is a gate that controls the output state of the buffer 17, and 24 is a gate that controls the output state of the buffer 19.

Hereinafter, each operation of modem initialization and abnormality detection of one carrier control line will be explained with reference to FIG. Note that the read/write clock 12-3 is set to "1" when reading, and "071" when writing.

(2) Initialization of the modem In order to initialize the modem before starting communication, the communication control program turns on the ER via the data bus 12-2 and puts an address signal on the address bus 12-2. The address signal is decoded by the decoder 13, and 111 II is set in the latch 14 via the gate 2o at the write timing of the read/write clock 12-3.

After that, the communication control program puts an address signal on the address bus 12-1 to read the DR to confirm that the modem has been initialized, and the address signal is decoded by the decoder 13 and read/write. At the read timing of the clock 12-3, the buffer 16 is enabled via the gate 21, and the output "1" of the latch 14 is output as DR to the data bus 12-2.

With this function, the ER instruction status can be displayed with the DR read instruction, and modem initialization at the modem interface can be simulated.

■ Carrier control Since the communication control program instructs carrier transmission, R8 is turned on via the data bus 12-2 and an address signal is placed on the address bus 12-1.The address signal is decoded by the decoder 13 and read. Latch 1 is passed through gate 22 at the write timing of the write clock.
5 is set to "1". As a result, signal bit channel 81 is set to 111''.

After that, the address bus 12-1 communication control program reads C8 to confirm that communication is possible.
When an address signal is placed on 1, the address signal is decoded by 13, the buffer 17 is enabled via the gate 23 at the read timing of the read/write clock, and the output "1" of the latch 15 is sent as C8 to the data bus 12-2. With the single function output to , it is possible to send out 81 bits in response to an RS ON instruction, and to simulate the instruction state of R8 in response to a C8 read instruction.

■ Line abnormality detection In normal state, when each bit of the signal bit channel on the signal line 11 is logically summed by the gate 18 (S,
is inverted and input to the gate 18), and the inverted output of the gate 18 becomes "1". Therefore, when the communication control program reads the CD to check the line status, when an address signal is placed on the address bus 12-1, the address signal is decoded by the decoder 13, and the gate 24 is activated at the read timing of the read/write clock. The buffer 19 is enabled via the gate 18, and the inverted output 1'1'' of the gate 18 is output to the data bus 12-2 as a CD.
~Ai= re 1 t''), gate 18
The inverted output of is "O11", and C and D are "0".

With this function, it is possible to simulate a line abnormal state display and a received carrier detection display.

Through the above operations, the character assembly/disassembly control section 3-1 and the signal bit channel control section 4 are controlled by the communication control program.
-1 control is equivalent to control when a conventional modem interface is accommodated. On the other hand, when controlling the connection with the network, the communication control program controls the character assembly control section 3-2, thereby enabling live broadcasting.

〔Effect of the invention〕

As explained above, according to the present invention, when accommodating a digital line in a communication control processing device, each signal of a signal bit channel is simulated as each signal of a modem interface, so that conventional modem interface control signals can be simulated. The digital interface can be controlled by the communication control program without making any changes to the communication control program.

[Brief explanation of drawings]

FIG. 1 is a plotter diagram showing an embodiment of a communication control processing device according to the present invention, FIG. 2 is a detailed diagram of a signal bit channel control section including a modem interface pseudo-circuit in FIG. 1, and FIG. 3 is a diagram of a digital line. FIG. 4 is a block diagram showing a communication control processing device containing a modem interface. 1... Line control unit (LC), 2... Processing unit (pu
). 3-1.3-2...Character assembly and disassembly control section. 4-1...Signal bit channel control unit, 6...Transmission frame assembly/disassembly control unit. 7... Modem interface pseudo circuit. 8...Digital line. Figure 4

Claims (1)

[Claims] (1) A line control unit that accommodates a digital line and controls the transmission and reception of transmission frames consisting of a data channel and a signal bit channel that displays line and network failure status and communication status, and supports various transmission control procedures. A communication control processing device comprising: a processing unit that controls the line control unit using a communication control program; A digital interface control method for a communication control processing device is characterized by making a digital line appear equivalent to a modem interface.