JPH08249137A - Printing system - Google Patents

Abstract

PURPOSE: To transfer much data at a comparatively high speed by providing this printing system with a data transfer means for transferring data by using plural virtual communication channels in an interface capable of executing bidirectional communication and handshaking means for executing handshaking by hardware in the bidirectionally communicatable interface. CONSTITUTION: A control part 11 switches data transfer to/from a host computer 2, allocates a communication channel and controls the operation of another recorder 1. A RAM 12 stores variables for controlling data transfer or communication channels, a receiving buffer, a bit map developing area, etc. A ROM 13 stores a program for executing bidirectional data transfer to be executed by simultaneously using plural communication channels and a program for controlling the operation of other recorders 1. An operation panel 14 is used for inputting and setting up a printing environment for the recoder 1. An interface 15 can execute bidirectional data transfer at a high speed. An engine 16 outputs printing data.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing system having an interface capable of bidirectional communication, and more particularly to a printing system which transfers data using a plurality of virtual communication channels.

[0002]

2. Description of the Related Art Conventionally, an interface for transferring a large amount of data such as image data which cannot be distinguished from a specific control code between a host computer and a printing apparatus and returning the status from the printing apparatus. For example, a bidirectional interface such as RS-232C is used.

[0003]

However, in the conventional printing system in which the above-mentioned bidirectional interface is used, for example, in the case of the RS-232C interface, it is necessary to specify the Xon / Xoff for the handshake. However, there is a problem that it cannot be distinguished from image data. Also, RS-2
Although the 32C interface can perform a handshake using a signal line, in that case, there is a problem that it takes time to transfer a large amount of data because the transfer speed is low. Furthermore, once you start transferring large amounts of data,
There is also a problem that the status of the recording device cannot be returned until the transfer is completed.

The present invention has been made in view of the above technical problems, and an object of the present invention is, for example, a bidirectional Centronics as an interface capable of bidirectional communication for transferring data between a host computer and a recording device. When using an interface, the handshake can be performed by hardware even during the transfer of image data, and a large amount of data can be transferred relatively quickly. Furthermore, the image data can be transferred via a certain communication channel. It is an object of the present invention to provide a printing system capable of returning the status of the recording device through another communication channel.

[0005]

SUMMARY OF THE INVENTION The present invention relates to a printing system for transferring print data from a host computer to a recording device and forming a print pattern on the recording medium by the recording device. An interface capable of two-way communication for performing transfer,
Data transfer means for performing data transfer using a plurality of virtual communication channels in a bidirectional communication interface, and handshake means for performing a handshake by hardware in the bidirectional communication interface. Thus, the above object is achieved.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a schematic configuration of an embodiment of a printing system to which the present invention is applied. In FIG. 1, 1
Is a recording device (printing device), and 2 is a host computer. The host computer 2 has an interface capable of bidirectional data transfer at high speed. The recording device 1 includes a control unit 11, a RAM 12, a ROM 13,
An operation panel 14, an interface 15 and an engine 16 are provided.

The control unit 11 includes a host computer 2
Switching of data transfer between and, allocation of communication channels,
The operation control of the other recording apparatus 1 is performed. The RAM 12 is for securing variables for data transfer or communication channel control, a reception buffer, an area for expanding a bitmap, and the like. In the ROM 13,
A program for performing bidirectional data transfer using a plurality of communication channels as described later with reference to FIG. 2 or a program for controlling other operations of the recording apparatus 1 is stored.

The operation panel 14 is for inputting and setting the printing environment of the recording apparatus 1. The interface 15 is an interface capable of high-speed bidirectional data transfer. The engine 16 is for outputting print data expanded into a bitmap.

FIG. 2 is a flow chart of the operation of returning the status from the recording apparatus 1 (printing apparatus) 1 of the printing system of FIG. 1 while receiving the image data. FIG. 3 is a flowchart of an operation in which the host computer 2 of the printing system of FIG. 1 requests the printer 1 to return the status while transmitting image data. Next, the operation of the printing system of the present invention having the configuration of FIG. 1 will be described with reference to FIGS.

Since the contents of operations such as data processing control, bit map expansion, and bit map output processing are the same as those of the known art, detailed description thereof will be omitted. Further, here, for the sake of simplification of description, bidirectional Centronics is used as an interface, and two communication channels, channel 0 and channel 1, can be used, and the printing device can be used during transfer of image data from the host computer 2. A case where the status is returned from 1 will be described.

1 to 3, first, in the recording apparatus (printing apparatus) 1, under the control of the control section 11, in step S11, a status request command reception waiting state from the host computer 2 is waited. ing. Here, when the status request command is received, step S1
2, the requested status is created on the RAM 12 according to the program stored in the ROM 13. Then, in step S13, the status on the RAM 12 is transmitted from the interface 15 to the host computer 2.

Here, channel 0 is used to receive the image data, and since the host computer 2 switches to channel 1 when transmitting the status request command, channel 1 is used as it is to transmit the status. Then, the procedure returns to step S11, and the status request command reception waiting state is again entered.

On the other hand, in the host computer 2,
In step S21, the status is waiting for a status request from the application program, and when a status request occurs, the process proceeds to step S22. Step S
At 22 it is checked whether channel 0 is in use. Since channel 0 is used here to transmit the image data to the printing apparatus (printer) 1, step S23 is performed.
Go to and switch the interface to channel 1. Then, the process proceeds to step S24, the status request is transmitted to the printing device (printing device) 1, and in step S25, the status response is waited for from the printing device (printing device) 1. When the status response is received, step S21
It returns to and returns to the status request waiting state.

[0014]

As is apparent from the above description, according to the present invention, in a printing system in which print data is transferred from a host computer to a recording device and the recording device forms a print pattern on a recording medium, An interface capable of bidirectional communication for transferring data to and from a recording device, a data transfer means for transferring data using a plurality of virtual communication channels in the interface capable of bidirectional communication, and a bidirectional communication Since the handshake means for performing handshake by hardware in a possible interface is provided, when a bidirectional Centronics interface, for example, is used as an interface capable of bidirectional communication, the handshake is performed while the image data is being transferred. In addition, a large amount of data can be transferred relatively quickly, and the status of the recording device can be returned through another communication channel while the image data is being transferred through another communication channel. A system is provided.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of an embodiment of a printing system to which the present invention is applied.

FIG. 2 is a flowchart of an operation in which the recording apparatus in FIG. 1 returns a status from the recording apparatus while receiving image data.

FIG. 3 is a flowchart of an operation in which the host computer in FIG. 1 requests the recording apparatus to return a status while the host computer is transmitting image data.

[Explanation of symbols]

 1 recording device (printing device) 2 host computer 11 control unit 12 RAM 13 ROM 14 operation panel 15 interface 16 engine

Claims (1)

[Claims] 1. In a printing system in which print data is transferred from a host computer to a recording device and a print pattern is formed on the recording medium by the recording device, bidirectional data transfer between the host computer and the recording device is performed. A communicable interface, a data transfer means for performing data transfer using a plurality of virtual communication channels in the bidirectional communication interface, and a handshake means for performing a handshake by hardware in the bidirectional communication interface, A printing system comprising: