JPS59169228A - Circuit switch control system - Google Patents

Abstract

PURPOSE:To simplify the constitution of a circuit switch control system by providing an information switch function of a controller to a circuit switching device in order to decrease the number of connections of a field construction as well as to use the system control bit to the control information of the switching device. CONSTITUTION:A circuit switching device LSW is provided between controllers ICU0 and ICU1 of each system and communication controllers CCE0 and CCE1 of each system of a multiplexed data communication system, and central processing units CPU0 and CPU1 of each system are connected to each of said controllers. An MODEM device (circuit device) MD is connected to the device LSW. Then the control information showing that the own system is under a switching operation is set to the switch control information. At the same time, a circuit consisting of an FF which selects the circuit switch control information with which the control bit is first turned on and a gate, etc. is provided to the device LSW together with a circuit which switches the MD by the switch control information. In such a way, the constitution is simplified for a circuit switch control system.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a line switching control system for a duplex data communication processing system.

Prior Art and Problems In data exchange, multiple lines are connected to the communication control unit CG'E, and the central processing unit CPU handles data sent from a terminal through one of the lines, and sends the data to the destination terminal via the line. The process of transmitting the data through the other one is performed. A system with increased stability so that it can continue operating even if a failure occurs in some of its circuit elements employs multiplexing of CPUs, CCEs, etc., and a conventional example is shown in FIG. 1st
The figure shows an example of a data communication processing system multiplexed into two systems, 0 system and 1 system, where CPU0. CPUI is the central processing unit of each unit, CCEO, CCEI are the communication control unit of each unit, ICU
O, ICUI is the control device of each unit, L, SW is the line switching device, ISW is the ICU information switching device, MD is the modem device,
SWC is a system switching device.

In this system, a control signal from the system switching device SWC that detects the status of the system (act, high) is used to switch the ICU information switching device ISW to the ICUO side if the 0 system is active, and to the ICUI side if the 1 system is active. Equipment ICUO
Alternatively, information from the ICUI (LSW control information) is given to the line switching device LSW. The line switching device LSW switches and connects the communication control device CCEO or CCEl to the modem device MD based on the information. For example, O type is act, 1
When the system is in standby, the SWC switches the ISW to the ICUn side and connects the L
SW connects MD to CCEO or to CCEl.

If the 0 system is active, the MD is often connected to the CCEO, but if there is a request to test a specific line in the standby system, in this case the MD is connected to the CCEI.

In any case, the switching command comes from the act system.

By the way, the system switching device SWC includes a central processing unit Cpuo,
C: Based on the act and standby information 914 of each group given from PU1, the ICU information switching device IsW is switched to the act side I.
Since the ICU information switching device ISW is only for switching to the CU, and the ICU information switching device ISW is only for switching, it would be wasteful to have these as independent circuit configurations as it would only make the overall configuration complicated and expensive. be. In the conventional system, the line switching device LSW simply performs the switching operation and does not have any special judgment ability, so it requires hardware such as SWC, ISW, etc. However, if the line switching device LSW has a judgment function, the SWC , ISW can be omitted, which allows cost reduction, miniaturization, etc.

Purpose of the Invention The present invention facilitates maintenance work by providing an ICU information switching function in the line switching device LSW, reduces connection cables during on-site construction, and uses LSW control control information system control bits. This is intended to simplify and downsize the system configuration by omitting the switching devices SWC and ISW.

Composition of the Invention The present invention provides a line switching device between a duplexed communication control device and a common line device, and also duplicates a central processing unit, so that switching control information from the duplexed central processing unit can be transmitted from the duplexed central processing unit. In a line switching control method for a data communication processing system equipped with a control device that sends data to the line switching control device,
A control bit indicating that the own system is in a switching control operation is set in the switching control information, and the line switching device includes a circuit for selecting the switching control information for which the control bit is turned on first; It is characterized by being provided with a circuit that performs line switching based on switching control information selected by the circuit,
This will be explained in detail below with reference to the illustrated embodiments.

Embodiment of the Invention FIG. 2 shows an embodiment of the present invention, in which the same parts as in FIG. 1 are given the same reference numerals. This example differs from FIG. 1 in two ways. One is that the ICU information switching function (selecting whether to use the information via the ICUO or the information via the ICUI) is provided in the line switching device LSW, thereby omitting the ICU information switching device 1sW. The ICU information switching device ISW shown in FIG. 1 uses a relay as a switching means in order to be able to switch with any signal.
Although it was provided separately from SW, in this example IcUllt
By setting f4 to information using, for example, an open collector type transistor contact, the ICU information switching device ISW can be made electronic, downsized, and housed in the line switching device LSW. The second point is that the LSW control information (ICU information) from the control units ICUO and ICUI, that is, the switching control information, includes a system control bit, which allows you to determine which system is active (in operation) or standby (waiting). The system switching device S performs the same function with priority on the act side by displaying
This eliminates the need for WC.

FIG. 3 is an explanatory diagram of the LSW control information, where the O-th bit CTL of fa) is the LSW control bit (system control focus).

When controlling the line switching device LSW, this control bit C
' Set TL to "'1". 1st to 3rd bits are O-type ICU
The first bit (7) STB is the strobe bit of the second and third bits. The second bit is CC
It is set to 1 (valid) when switching to EO, and the third bit is set to 1 when switching to CCEl system. However, if both are 0 (invalid) or 1 (valid), both are invalid. The 4th to 6th” focuses are related to the 1st system ICUI, and the meaning of each bit is the same as the θ system.
The control information is in each scroll saw, and the control bit CTL is set to 1.
The party who made the change has control. FIG. 3 (bl is a time chart, which shows that the switching operation is performed at the rising edge of the strobe bit STB.

FIG. 4 is a configuration diagram of the LSW control information switching circuit provided in the line switching device LSW, where AO is a switching section that receives θ-system LSW control information via the control device ICUO, and A1 is a switching section that receives the LSW control information via the control device ICUO. This is a switching unit that receives system LSW control information. Taking the switching unit AO as an example, control pin 1
- If CT'L is 1, flip-flop FFO is sent, tri-state buffer TSO is turned on and ST
B.

CCEO, CCE'l are shown in Figure 5 (al's control circuit CNT
Output to. The same applies to the switching unit A1, where FF1 is a flip-flop that enables its own system, and TS1 is a tri-state buffer. However, if the other side is controlled first, control of the own system is prevented, and mutual flip-flop FFO is used.

The Q output of FF1 is used as an opening/closing control signal for the opponent's input game (Gl, GO). That is, if the O system controls first, d of the flip-flop FFO becomes L (low) level,
Even if the 1st system tries to control by closing the AND gate G1,
The cTL,='x is blocked by the AND gate G1 and does not reach the flip-flop FF1, and the FFI is not sent. Therefore, control remains in the O system's hands. When the 0 system sets the CTL bit to 0, the FFO is reset, so the 1 system can send the FFI to 7 and take control.At this time, the Q of the FFI becomes L, so the AND gate G
O is closed and the 0 system cannot cent FFO. Furthermore, ROI
, RO2, R11, R1, 2 are receivers of LSW control information, DO, Di are control flip-flops FFO, FF.
This is a driver for I state read (CTL read).

FIG. 5(a) shows a specific example of the control circuit CNT provided in the line switching device LSW, in which Gil to G14 are AND gates, G15. G16 is an OR gate, and FF is a flip-flop for line switching. The Q output X of this flip-flop nib FF is the gate circuit G20. G21
(The main part of the line switching device LSW, shown as a switch in FIG. 2), and line switching is performed at the H (high) level and L level.

G22 is an or gate. Since there are generally multiple lines, these are shown as xn in the figure.

Switching is performed simultaneously for n lines.

The LSW control information shown in Fig. 3 (1a) has 8 bits, of which the 0th bit is the CTL bit, the 1st to 3rd bits are control information from the O system, the 4th to 6th bits are control information from the 1 system,
The 7th bit is play. In the case of 0 system control, the 4th
The ~6th bit is a play, and in the case of 1-system control, the 1st to 3rd bits are a play, but these are kept the same content.

Next, the overall operation will be explained with reference to FIG. The LSW control information is sent from the central processing units cpuo and cPut of each prefecture, and is transferred to the switching units AO and AI (FIG. 4) of the line switching unit LSW via the control units ICUO and ICU1. On the other hand, when transmitting line data, the central processing unit CPU0. C
The data is transmitted from the PUI to the communication control units CCEO and CCEI, where it is parallel-serial converted and sent out to the line through the line switching unit LSW and modem unit MD. At the time of reception, the route is the opposite.

Now (control bit C included in the 11L SW control information)
When TL is set to 1, the flip-flop FFO in Fig. 4,
The corresponding side of the FFI is sent, and a path to the control circuit CNT shown in FIG. 5(a) is formed. (2) Next, read the LSW control bit (CTL read). This allows the state of the flip-flop to be read. If it is 0, it means that other systems are being controlled, so take your timing and go back to +11. 1
If so, it can be controlled.

(Program 31CCEO, CCEI, and STB as 1/9 according to the time chart in FIG. 3(b).

At this point, a path to the control circuit has already been formed.

(4) When switching control is completed, control beep) CTL is set to 0, and the above path is cut off (Q output of the corresponding flip-flop is set to O).

Effects of the Invention As described above, the present invention has advantages such as simplifying and downsizing the configuration of the data communication processing system, facilitating maintenance work, and eliminating connection cables during on-site construction.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a data communication processing system that employs a conventional line switching control method, FIG. 2 is a block diagram showing an embodiment of the present invention, and FIG. 3 is an explanatory diagram of LSW control information.
FIGS. 4 and 5 are configuration diagrams of each part within the line switching device. In the figure, CPU0. CPUI is a central processing unit, CCEO,
CCEI is a communication control device, ICUO, ICUI are control devices, LSW is a line switching device, MD is a modem device (line device), FFO, FFI are flip-flops for switching control bits, GO, GI are gates for double selection prevention. It is a circuit. Applicant Fujitsu Ltd. Representative Patent Attorney Minoru Aoyagi Figure 1 Figure 2 Figure 3 @ Figure 4

Claims (1)

[Claims] A line switching device is provided between the duplexed communication control device and the common line device, and the central processing unit is also duplexed, and switching control information from the duplexed central processing unit is transmitted to the designated area. In a line switching control method of a data communication processing system equipped with a control device that sends data to a line switching control device, a control bit indicating that the own system is in a switching control operation is set in the switching control information, and the line switching A line characterized in that the device is provided with a circuit for selecting switching control information for which the control pin is turned on first, and a circuit for switching the line based on the switching control information selected by the circuit. Switching control method.