JPH0383674A - Remote control changeover printer - Google Patents

Abstract

PURPOSE:To mode possible the connection of a single printer to printer control devices by providing driver/receiver circuits, line changeover control circuits, line switching circuits, data code decoding circuits and line changeover cancellation circuits. CONSTITUTION:If occupancy request signals 103, 104 for connecting a printer 1 to printer control devices 2, 3 are entered from the printer control devices 2, 3 a data/control line is changed over, for example, so that the occupancy request signal 103 received initially is connected to the first printer control device 2 which receives the signal. In addition, a data code decoding circuit 14 detects cancellation code in received data, and disconnects the data/control line in a connected state when the cancellation code is decoded. A line changeover control circuit 12 selects a printer control device based on a received occupancy request signal next and enters information to a printer 1 from the selected printer control device by repeating the same action.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a system for controlling two or more printers.
This invention relates to the control of a remote control switching printer device for use in a device.

[Prior Art] Conventionally, printer devices have been used as information output devices in OA4M devices such as personal computers and word processors, and a plurality of OA devices are generally connected to this printer device as a printer control device. . In this case, −
In order to connect a plurality of printer control devices to one printer device, a switching device is provided between the two printer control devices.

[Problems to be Solved] However, using a switching device to connect a conventional printer device and a printer control device causes the following problems. That is, since which printer control device is connected to the printer device is manually operated using a switch, the switch may be accidentally switched during printing, and this switching device causes erroneous operation of printer output.

In addition, switching devices must be provided in correspondence with the number of printer control devices, and since they are provided separately,
There was a problem that the system was expensive.

The present invention has been made in view of the above problems, and allows connection of one printer device and multiple printer control devices by remote control of the printer control device without using a separate switching device. An object of the present invention is to provide a remote control switching printer device.

[Will Solution] In order to achieve the above object, a remote control switching printer device according to the present invention is provided corresponding to a plurality of printer control devices connected to one printer device, and the remote control switching printer device according to the present invention is provided corresponding to a plurality of printer control devices connected to one printer device, a plurality of driver/receiver circuits that transmit and receive data/control lines between the printer device and the printer device;
a line switching control circuit for inputting an occupancy request signal from a printer control device and selectively controlling a data/control line connected to one of the printer control devices via the driver/receiver circuit according to instructions of the occupancy request signal; , a line switching circuit that switches data/control lines based on a control signal of the line switching control circuit, and a data code decoding circuit that deciphers a release code for disconnecting the line embedded in the data from the printer control device. , and a line switching release circuit that releases the line between the print control device and the printer device in response to instructions from the data code decoding circuit.

[Operation] According to the above configuration, when occupancy request signals for connection with the printer device are input from a plurality of printer control devices, for example, the connection is made with the printer control device that sends the first occupancy request signal received. The data/control lines are switched to

The data code decoding circuit also detects a release code in the received data, and releases the connected data/control line when the release code is decoded.

Then, the line switching control circuit selects the printer control device that receives the next occupancy request signal, repeats the same operation as described above, and inputs information from the selected printer control device to the printer device.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

Fig. 1 shows a configuration block of a remote control switching printer device in which two printer control devices such as personal computers are connected, and Fig. 2 shows the appearance of the connector side of the printer device. .

In FIG. 1, a first printer control device 2 and a second printer control device 3 are connected to a printer device 1 via a centronics interface (not shown), as shown in FIG. , by connecting the first control device cable 101 and the second control device cable 102 using a Centronics interface connector.

In addition, a first driver/receiver circuit 10 and a second driver/receiver circuit 11 are provided in the printer device 1 in correspondence with the first printer device 2 and the second printer device 3. A line switching control circuit 12 and a line switching circuit are connected to the first driver/receiver circuit 10 and the second driver/receiver circuit 11. The line switching control circuit 12 receives the occupancy request signal transmitted from the printer control device, and in the embodiment, the data/control line is connected to another printer control device.
Busy (BU) output when the device is occupied
SY) signal to each printer control device.

FIG. 3 shows the arrangement of the connector bins of the Centronics interface. In the embodiment, the 14th bin is for the occupancy request signal (103°104), and the 11th bin is for the busy signal (105, 108). ).

Further, a data code decoding circuit 14 is connected to the line switching circuit 13, and print data supplied from the line switching circuit 13 is inputted to the printer printing device 15 via the data code decoding circuit 14. The data code decoding circuit 14 stores a remote state release code set in advance by a switch or the like, and by reading this release code, the remote state can be released.

Therefore, a line switching release circuit 16 is connected to the data code decoding circuit 14, and the line switching release circuit 16 outputs a release signal to the line switching control circuit 12.

The embodiment has the above configuration, and its operation will be explained below.

First, when requesting printing, the first and second printer control devices 2-3 activate the occupancy request signal and transmit it to the printer device 1 via the cables 101 and 102. Then, the printer device 1 receives the occupancy request signal at the first driver/receiver circuit 10 or the second driver/receiver circuit 11, and connects the first occupancy request signal line 103 to the second tumulus request signal line 104. The line switching control device 12 is notified of the occupancy request via the line switching control device 12.

This line switching control device 12 instructs the line switching circuit 13 to switch to the printer control device that first requested the connection, for example, to switch to the first printer control device 2. In the embodiment, if two occupancy request signals are input at the same time, priority is given to the side that was connected last time.

In addition, when printing is already in progress on one side, for example, on the second printer control device, the line switching control circuit 12 sends a busy signal to the first printer control device on the busy signal line 105 (or 106 in the opposite case). ). Note that this busy signal (105, 106) is also used by the printer printing device 15, so the first driver/receiver circuit 10 or the second driver/receiver circuit 11
It is in a wired-or state.

In this way, for example, when a request for occupancy of the first printer control device 2 is accepted, the line is changed to input data from the first printer control device 2 in the line switching circuit 13. Switched printer printing device 1
5, the data sent from the first printer control device 2 will be printed, and a release code for releasing the remote state is added to the end of the print data, and the data code decoding circuit At step 14, the above release code in the data is detected.

Note that the release code in this case is configured not to be printed.

When the transmission of data from the first printer control device 2 is completed and the above-mentioned release coat is detected, the line switching control circuit 1
For example, if a busy signal is being sent to the second printer control device 3 side, the busy state is canceled and a request for occupation of the second printer control device 3 is not accepted. Then, printing will be performed in the same manner as above.

[Effects of the Invention] As explained above, according to the present invention, data/control lines from a plurality of printer control devices can be switched by remote control in a printer device. It is no longer necessary to use a switching device.

As a result, erroneous operations in printer operation are prevented, reliability is improved, and the number of cables can be reduced, so that the system can be constructed at a low cost.

[Brief explanation of drawings]

Fig. 1 is a configuration block diagram of a remote control switching printer device according to an embodiment of the present invention, Fig. 2 is an external view of the embodiment device on the connector side, and Fig. 3 is a connection with a printer control device in the embodiment. FIG. 3 is a connector pin layout diagram of the Centronics interface used in the 1: Printer device 2: First printer control device 3: Second printer control device 102 First driver/receiver circuit 11: Second driver/receiver circuit 12 Two-line switching control circuit 13 Two-line switching circuit 14: Data code decoding circuit 15: Printer printing device 16: Line switching release circuit 101.102: Cable 103: First occupancy request signal line

Claims (1)

[Claims] A plurality of driver/receiver circuits that are provided corresponding to a plurality of printer control devices connected to one printer device and that transmit and receive data/control lines between the printer control device and the printer device; a line switching control circuit for inputting an occupancy request signal from a control device and selectively controlling a data/control line connected to one of the printer control devices via the driver/receiver circuit according to instructions of the occupancy request signal; a line switching circuit that switches data/control lines based on a control signal of the line switching control circuit; a data code decoding circuit that deciphers a release code for line connection release that is embedded in the data from the printer control device; A remote control switching printer device comprising a line switching release circuit that releases the line between the print control device and the printer device according to instructions from the data code decoding circuit.