JPH05216602A - Information processing system - Google Patents

Abstract

PURPOSE:To permit the only required printer to print without providing a switching device in the information processing system containing printers and host devices. CONSTITUTION:Identification informations dissimilar to each other are given to a plurality of printers. The identification information of the printer to be printed is sent from the host device to signal lines for printing data by means of the DTMF analog data. The binary printing data is also transmitted. In each printer, the identification information is decoded by a decoder 3, and when the decoded information coincides with the identification information of the its own device, the binary printing data coming in later is read by a data reading section 5 and printed.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an information processing system, and more particularly to an information processing system in which a plurality of printer devices are connected to one host device such as a host computer.

[0002]

2. Description of the Related Art Conventionally, a parallel interface of a printer device in an information processing system of this type has at least eight data lines for transmitting binary data,
It has one data strobe signal line and one busy signal line for synchronizing the transmission of binary data.

For data transfer of binary data, a data transmission device such as a host computer sets 1 byte (8 bits) of data on eight data lines, and then a data strobe for synchronizing the data transfer. The signal is asserted by the data delivery device to the printer device. The printer device asserts a busy signal to the data sending device when the data strobe signal is asserted.

The printer device has a valid 1 on the data line.
After receiving the data of byte (8 bits), the data sending device is negated with the busy signal to notify that the next data can be received.

FIG. 4 shows a timing chart of the parallel interface in the conventional printer device. This Figure 4
7, the data strobe is asserted after the data setup time, the data on the data line becomes valid, and the busy signal is asserted.

Then, the printer is held for a predetermined time or more and received by the printer side. After that, the busy signal is negated.

In the data transfer by the parallel interface of the conventional printer device, since the handshake (data communication) is performed with the data strobe signal and the busy signal, one byte (8
Only bit data transfer was possible.

Further, when an attempt is made to increase the data transfer rate, the pulse width of the data strobe and the setup time and hold time of the valid data of the data line with respect to the data strobe are specified, so the specified values are ignored. It was not possible to transfer such high speed data.

When a plurality of printer devices are connected to one host device, it is necessary to provide a switching device for selecting the printer device. If the switching device is not provided, all printers print the same print data, which is inconvenient.

However, the provision of such a switching device has a drawback that the cost is high and the operation for switching is troublesome. Therefore, there has been a demand for a system capable of printing only one printer device without providing a switch.

[0011]

SUMMARY OF THE INVENTION It is an object of the present invention to perform information processing in which, when a plurality of printer devices are connected to one host device, only a desired printer device can print without providing a switch. It is to provide a system.

[0012]

An information processing system according to the present invention includes a plurality of printer devices that receive print data to which different identification information is added, identification information of printer devices to be printed among these printer devices, and print data to be printed. And a receiving unit that is provided in each of the printer devices and receives the identification information from the upper device, and the identification information that is provided in each of the printer devices and received by the receiving unit identifies the own device. It has a printing means for printing the print data sent after it matches the information.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of the main part of an embodiment of a printer in an information processing system according to the present invention. In the figure, the interface portion of the printer device is shown.

The interface in the printer apparatus of this embodiment is for transmitting eight data lines for transmitting binary data, a data strobe signal line for synchronizing the transfer of binary data, and sending a busy signal to the host side. It is a parallel interface having a busy signal line. Further, this interface uses a well-known DTMF (Dual-Tone Multi Frequenc) for at least one data line of the binary data transmission during the period when the handshake of the binary data transfer is not performed.
The decoder 3 is configured to receive 4-bit data encoded by the y) method as an analog signal and decode the analog signal.

Further, this interface is sent from the host device via the DTMF signal reception notifying unit 4 which holds the identification information of its own device and compares the identification information with the decoding result of the decoder 3, and the data line. When the comparison result in the binarized data latch unit 1 for latching the print data and the reception notifying unit 4 indicates a match, the data reading unit 5 for reading the print data latched in the latch unit 1 and the data strobe signal And a busy signal control unit 2 which sends a busy signal back to the host device in response to the input.

The interface configured as described above is provided in each of the plurality of printer devices and receives print data from the host device. Then, the printing operation (not shown) is performed on the received print data.

The operation of the interface thus configured will be described with reference to the timing chart of FIG.

First, a host device (not shown) sends identification information based on DTMF analog data to one of the eight data lines. This identification information is the identification information of the printer device that is to perform the printing operation among the plurality of printer devices. After the identification information is decoded by the DTMF signal decoder 3 in each printer device,
It is sent to the DTMF signal reception notification unit 4. The reception notification unit 4 compares the held identification information of its own device with the decoded data.

If the comparison result shows a match, it can be recognized that the print data sent next is addressed to the own device. On the other hand, if the comparison result shows a non-coincidence, it can be recognized that the print data sent next is addressed to a printer device other than the own device.

When the comparison result shows a match, the notifying unit 4 notifies the data reading unit 5 to that effect.

After the notification, 8-bit binary data is sent via the data line and the data strobe signal is asserted, whereby the data latch unit 1
The binarized data is latched at.

Further, the data reading section 5 reads the binary data from the data latch section 1 and negates the busy signal. This is the end of the operation.

As described above, if the interface of this example is provided in each of the plurality of printer devices, the print data can be printed only in one of the printer devices. The data on the data line in the period in which the data strobe signal is not asserted is invalid data for the data latch unit 1.

A method of receiving the identification information after latching all the data is also conceivable. In this case, the operation is as follows.

Referring to the timing chart of FIG. 3,
Binary data is output from a data transmission device (not shown) such as a host computer to the data line of the parallel interface of the printer device, and the data strobe signal is asserted.
The binarized data is latched at. Next, when the data strobe signal is asserted, the busy signal control unit 2 notifies the data reading unit 5 that the binarized data has been received, and asserts the busy signal line of the parallel interface of the printer device. .

The data reading unit 5 reads the binarized data transferred from the data transmission device from the binarized data latch unit 1 and notifies the busy signal control unit 2 that the data reading is completed. Then the busy signal controller 2
Negates the busy signal on the parallel interface. As a result, data transfer of 1 byte (8 bits) is completed by means similar to the parallel interface of the conventional printer device.

Next, when an attribute (for example, printer identification information) is added to the data, the DTMF signal decoding unit 3 connected to at least one data line after the data transfer is sent from the data sending device to the DTMF. The 4-bit data encoded by the method is transmitted as an analog signal.

The DTMF signal decoder 3 is a DT for the data line.
When the MF signal is detected and decoded, the DTMF signal reception notifying section 4 compares the identification information with each other. If the comparison result shows a match, the data reading unit 5 is notified that the data has been received.

Upon being notified by the DTMF signal reception notifying unit 4, the data reading unit 5 reads 4-bit data from the DTMF signal decoder 3 and the data transfer is completed. As a result, the attribute can be added to the 1-byte (8-bit) data by using the DTMF signal, and only one of the plurality of printer devices can print.

In each of the above-described embodiments, the number of data lines for transferring the DTMF signal is one, but by using two lines, a total of 8 bits of data can be transferred, and the DTM signal can be transferred.
By assigning a bit weight to the DTMF signal decoding unit 3 connected to the data line that transfers the F signal,
It is possible to transfer 1-byte data.

Since there are eight data lines of the parallel interface of the printer, it is possible to transfer a maximum of 4 bytes of data at the same time by the DTMF signal.

As described above, by providing the decoder of the analog data signal encoded by the DTMF method on the data line of the parallel interface of the printer, attributes such as identification information can be added to the binary data. is there.

Further, by connecting the decoders of the DTMF signals to the eight data lines of the parallel interface of the printer, respectively, 4-byte data can be transferred at the same time.

Furthermore, since the DTMF signal is used in this example, the number of data lines and the like is the same as that of the conventional interface. Therefore, the connector and the cable can be compatible with the conventional ones.

However, it is obvious that a signal line for an attribute signal may be added without using the DTMF signal.

[0037]

As described above, according to the present invention, identification information is provided to each of a plurality of printer devices, and only the printer device provided with the identification information that matches the identification information sent from the higher-level device. By printing the data,
This has the effect of eliminating the need for a switch of the printer device.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a main part of a printer device in an information processing system according to an embodiment of the present invention.

FIG. 2 is a timing chart showing an operation example of a system including the printer device of FIG.

FIG. 3 is a timing chart showing another operation example of a system including the printer device of FIG.

FIG. 4 is an operation timing chart of a parallel interface in a conventional printer device.

[Explanation of symbols]

 1 Binarized data latch unit 2 Busy signal control unit 3 DTMF signal decoder 4 DTMF signal reception notification unit 5 Data reading unit

Claims (2)

[Claims] 1. A plurality of printer devices that receive print data to which different identification information is added, a host device that transmits the identification information of the printer device to be printed and the print data to be printed among the printer devices, and Receiving means provided in each of the printer devices for receiving the identification information from the higher-order device, and sent after the identification information provided in each of the printer devices by the receiving means matches the identification information of the own device. An information processing system comprising: a printing unit that prints incoming print data. 2. The host device sets the identification information to DTM.
2. The information processing system according to claim 1, further comprising means for transmitting to the print data signal line by the F method.