JP2004013429A - Data control method and recorder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To aim at normal printing in either of a case of receiving packeted data on the basis of an IEEE 1284.4 protocol and a case of receiving data of a conventional stream method. <P>SOLUTION: Discrimination is made on whether data transmitted to an interface control channel in communication by the IEEE 1284.4 protocol is 1284.4 packeted data or a non-packeted image data command group by analyzing 6 bites of the forefront, and in non-packeted data, the discrimination is repeated up to detecting the forefront of the next packet while performing the prescribed bite number of processings to a rear stage. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
1. Field of the Invention The present invention relates to a recording apparatus, and more particularly, to processing of recording data at the time of receiving packet data specified by the IEEE1284.4 protocol and processing of receiving conventional data without a plurality of logical channels.
[0002]
[Prior art]
First, the IEEE1284.4 protocol will be described. The IEEE1284.4 protocol defines a point-to-point protocol used for a layer above the physical interface layer and below the application layer. These layers have the functions and features of the transport and session layers as indicated by the OSI reference model. This protocol shall function on the IEEE1284-1994 interface, but may also function on another point-to-point interface. What is required of the physical interface to implement the IEEE1284.4 protocol is that bidirectional communication is possible. The IEEE1284.4 protocol establishes a logical communication path (channel) on the interface, and It implements bidirectional communication for one channel.
[0003]
In the IEEE1284.4 protocol, the ends of the transmission-side device and the reception-side device are called PrimarySocketID (PSID) and SecondarySocketID (SSID), respectively, and the flow path of data to which the respective SocketIDs are connected is a communication path (channel).
[0004]
The IEEE1284.4 protocol employs a packet method as a data transfer method. The packet method transmits packet data composed of a header portion indicating a data length and a data portion including data itself as one data group. In the IEEE1284.4 protocol, this packet header is specified as 6 bytes, and a maximum of 64 k-6 bytes of data can be transmitted as a data group.
[0005]
However, this packet size determines the maximum transferable length, and the packet data actually transferred may not satisfy this size. Therefore, the data length included in the packet data is described in the packet header. When the receiving device receives the packet, based on the data length indicated in the header portion, the data portion and the packet data are compared. Processing such as recognizing a break, extracting data from the recognized data portion, and storing the data in a memory in the device is performed.
[0006]
More specifically, the packet circulating on this communication path (channel) has a structure as shown in FIG. 2, and the transmitting device and the receiving device determine on which communication channel (channel) by the PSID and SSID included in the header portion. It is determined whether or not the packet is transmitted. Each Socket ID is allowed to have a value of 0 × 00 to 0 × FF, but PSID = 0 × 00 and SSID = 0 × 00 are the first communication paths (channels) and are reserved as interface control channels. Have been. This interface control channel is mainly used for interface management, and other channels are dynamically established by an OpenChannel / OpenChannelIReply command after negotiating a packet size on the interface control channel.
[0007]
A specific example will be described in which the transmitting device side on the IEEE1284.4 protocol establishes a data transfer channel, transmits recording data on the channel, and generates image data by the receiving device.
[0008]
First, as the configuration of the transmitting device side (host computer), it is assumed that an application, a printer driver main, a renderer, a spooler, and a packetizing module exist as shown in FIG. These are provided by an application for creating an image to be printed by the user, a printer driver main activated by a user's print instruction, a renderer for converting image data on the application into bitmap data according to an instruction from the printer driver main, and a printer driver. A spooler for spooling the storage device control command and the data obtained by converting bitmap data from the renderer into a command to a file on the hard disk, reading the above-mentioned command group from the spooled file, generating IEEE1284.4 packets, and generating an appropriate channel Is a packetization module that transmits data to The packetization module also has the function of dynamically creating the required channels. The packetization module also controls the receiving device and manages the interface based on instructions from the user in addition to the image data, and this module establishes a data transmission channel. ing.
[0009]
In the IEEE1284.4 protocol, when a transmitting device and a receiving device are connected, only an interface control channel can be used as a communication path. Therefore, it is desirable that the packetization module dynamically establish a channel for data communication when print data is generated. Here, before establishing a new channel, a ConfigSocket command must be issued through the interface control channel to specify the packet size for this channel. If the transmitting device attempts to set the packet size for this data channel to 1 KByte, it issues a command with "1 KByte" written in the ConfigSocket command. If the receiving device can accept this packet size when receiving this command, it may issue "1 KByte" in the ConfigSocketReply command and issue the command to the transmitting device. It is also possible to issue a command by describing a smaller value.
[0010]
When the transmitting device receives this ConfigSocketReply command, the smaller the packet size in the ConfigSocket command issued by itself and the smaller the packet size in the ConfigSocketReply command issued by the receiving device, the maximum packet size that can be transmitted to this data transmission channel. Will be operated thereafter. Thereafter, the transmitting device issues an OpenChannel to the interface control channel, and the data transmitting channel is established when an OpenChannelReply command is received from the receiving device. Thereafter, image data is transmitted through the data transmission channel, and the recording apparatus generates an image from the data on the data transmission channel.
[0011]
As described above, the IEEE 1284.4 protocol is based on the premise that packetized data is transmitted. This packet defines a command group for controlling the above-described recording apparatus and transmitting image data in advance. A packet header is divided into appropriate sizes within the specified size range, and packet headers are attached. If the headers of a plurality of consecutive packets are removed (depacketed) and connected, they are completely equivalent to the data of the conventional stream system. A data group is obtained.
[0012]
By the way, the recording apparatus before implementing the data transfer by the packet system such as the IEEE1284.4 protocol generally used the stream system data transfer represented by the conventional Centronics interface. In the Centronics interface, there is no concept of a channel, and data transfer is always one-way from the transmitting device to the receiving device on one transit path. Further, the data flowing on the communication path has been transmitted as a data string called a stream having no limitation on the data length.
[0013]
The configuration of the conventional transmitting device (host computer) created on the assumption that such a Centronics interface is used is basically the same as that of FIG. 3, but there is no packetization module and the spooling is performed. Image data was transmitted by another module over the Centronics interface. Further, as a function of the printer driver, it is possible to divert the image data by "storing the spooled data in a file" and transmit it by a DOS COPY command or the like. In this case, since the host computer does not use a driver corresponding to the IEEE1284.4 protocol such as DOS, image data is transmitted without newly establishing a data transmission channel. In this case, on the receiving device side, unpacketized data is transmitted to the interface control channel, so that it is treated as a packet error as it is.
[0014]
[Problems to be solved by the invention]
As described above, the configuration of the conventional transmission device side does not establish a data transmission channel for the recording data spooled by the spooler and transmits the data to that channel. And the same print result could be obtained when transmitted by the DOS COPY command. However, when the IEEE1284.4 protocol is implemented, the recording data is further packetized by the packetizing module of the spooled data, and if the data is not transmitted to the data transmission channel, the receiving device discards the data as a packet error and discards the data. I will.
[0015]
The present invention has been made in view of the above-described problems, and when conventional compatible data that is not packetized and stored in a file is received on an interface control channel, the data is not prepared as a data error but is originally prepared for recording data communication. By writing the data in the buffer memory using software, printing using a COPY command, which is one of the DOS commands, is also enabled.
[0016]
[Means for Solving the Problems]
In order to achieve the above object, a recording apparatus of the present invention has a physical interface capable of bidirectional communication such as USB, IEEE1284, etc., and a protocol control means for controlling a plurality of logical channels defined in IEEE1284.4; One of the logical channels is used as a channel for interface control, a packet analysis unit for analyzing a control packet received on the channel, an interface control unit for establishing a new channel in addition to the interface control channel, and When the established channel is a channel for recording data communication, depacket means for removing a header portion of a data packet received on the communication channel, a buffer memory for holding the depacketed data, For hardware such as DMA Means for writing data to the buffer memory, and print data analyzing means for generating a print image from the data held in the buffer memory. When the recording data is received through the communication channel, the depacket unit and the data storage unit hold the recording data in the buffer memory, and the recording data analysis unit generates a recording image. If data without an IEEE1284.4 packet structure is received on an interface control channel without a channel being established, the packet analysis means writes the received data to the buffer memory in software, and the packet analysis means Until it finds a new packet header. Repeating, characterized.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail and specifically with reference to the drawings.
[0018]
FIG. 3 is a conceptual diagram of an interface when a recording apparatus according to the present invention and a host computer for transmitting image data are connected. The recording device 304 of this embodiment is connected to the host computer 301 by a plurality of logical channels 303 established on the physical interface 302.
[0019]
When the physical interface is connected for the first time, there is only one logical channel as shown in FIG. 2A, and data transmitted on this channel is received by the protocol control means 401 and passed to the packet analysis means 403 as a packet. It is. The packet analysis unit 403 analyzes the command of the received packet, and establishes a new data transmission logical channel 305 on the physical interface 302 by using the interface control unit 402 if necessary.
[0020]
Next, an operation when receiving packetized image data based on the IEEE1284.4 protocol from the host computer will be described.
[0021]
FIG. 4 is a block diagram of a recording apparatus according to the present invention. In particular, FIG. 4A shows that in the recording device 304 of this embodiment, after a logical channel for data transmission is established, data transmitted from the protocol control unit to a recording unit (not shown) is transmitted on the data transmission channel. Shows the flow.
[0022]
When the physical interface is USB, the protocol control means 401 has a function of removing the header part of the USB packet and passing only the data part to the packet analysis means 403. When the physical interface is IEEE1284, it performs a handshake process defined in the standard and passes it to the packet analysis unit 403 byte by byte.
[0023]
After establishing a logical channel for data transmission according to the procedure described above, the data transmitted on this data transmission channel is identified as a packet transmitted in accordance with the IEEE1284.4 protocol. The packet transmitted on the channel is analyzed. When the packet analyzing unit 403 recognizes that the analyzed packet is a packet transmitted on the data transmission channel, it has a function of passing the packet to the depacketing unit 404.
[0024]
The depacket unit 404 has a function of removing the header part from the passed packet and storing only the data part in the buffer memory 405 by hardware such as DMA (not shown).
[0025]
The recording data analysis means 406 always monitors the buffer memory 405, and when the data is stored in the buffer memory 405, reads out the data one by one, and the recording means (not shown) most suitable for recording the recording data. The data is converted into a format and stored in the print buffer 407.
[0026]
Next, an operation when image data is received by the stream method without establishing a new data transmission channel from the host computer will be described.
[0027]
FIG. 4B shows a recording unit (not shown) from the protocol control unit for data transmitted as conventional stream system data without establishing a logical channel for data transmission in the recording device 304 of this embodiment. The flow up to this point is shown.
[0028]
On the receiving device side, the data received before the logical channel for data transmission is established is regarded as a packet transmitted to the interface control channel, so the packet analysis means 403 determines the PSID / SSID of the packet header. Are both 0 × 00. If both are 0x00, it is regarded as normal packet data and the corresponding processing is executed. If either PSID / SSID is not 0x00, the data is recorded data analysis means. The data is sent to 406 and handled as stream data.
[0029]
As described above, the packet analysis unit 403 analyzes the received data, and determines whether the data is an interface control command or a stream data, so that the image data transmitted by the DOS COPY command or the like can also be used in the recording apparatus. Can be printed, but the packet analysis means 403 makes this determination in the step shown in FIG. That is, the packet analysis means 403 analyzes 6 bytes which are considered to be the header part of the received data in Step 1, and determines whether this data is an interface control packet from PSID / SSID (Step 2). If this is an interface control command, a process corresponding to the command is executed, and the process returns to Step 1 again. If the PSID / SSID included in the 8 bytes is not a channel that is already open, it is transferred to the recording data analysis unit 406 (Step 4), and the recording data analysis unit 408 analyzes the data as command group stream data. I do. The recording data analysis means 406 analyzes the stream data, and when detecting the end of the command, issues an event to the interface control means and returns to Step 1 again.
[0030]
【The invention's effect】
As described above, the recording apparatus of the present embodiment can transmit data using the data transmission channel in the interface having a plurality of logical channels based on the IEEE1284.4 protocol, and can use the conventional printer driver or the like. Normal printing can be performed even when data of a stream method for transmitting data without transmitting a plurality of created logical channels is transmitted.
[Brief description of the drawings]
FIG. 1 is an operation flowchart of a data control method according to the present invention.
FIG. 2 is a packet structure defined in IEEE1284.4.
FIG. 3 is a conceptual diagram of an interface of a recording apparatus according to the present invention.
FIG. 4 is a block diagram of a recording device according to the present invention.
FIG. 5 is a configuration diagram of a transmission device that generates data to be printed by a recording device according to the present invention.
[Explanation of symbols]
301 Transmission equipment (host computer)
302 Physical interface (USB, IEEE1284)
303 logical channel 304 recording device 401 protocol control means 402 interface control means 403 packet analysis means 404 depacket means 405 buffer memory 406 print data analysis means 407 print buffer

Claims (1)

A protocol control means having a physical interface capable of bidirectional communication such as USB, IEEE1284 or the like, and controlling a plurality of logical channels defined by IEEE1284.4;
Packet analysis means for analyzing packets flowing on the logical channel;
An interface control means for setting one of the plurality of logical channels as an interface control channel and establishing a new channel in addition to the other logical channel;
When the established channel is a channel for recording data communication, depacket means for removing a header portion of a data packet received on the communication channel;
A buffer memory for holding depacketed data,
Data storage means for writing the depacketed data to a buffer memory by hardware such as DMA,
Recording data analysis means for generating a recording image from the data held in the buffer memory,
A channel for recording data communication is established by a regular procedure, and when recording data is received on the recording data communication channel, the recording data is held in the buffer memory by the depacket unit and the data storage unit. A recording image is generated by the data analysis unit, but when data without the IEEE1284.4 packet structure is received on the interface control channel without establishing a recording data communication channel, the packet analysis unit Transferring the received data to the recording data analysis means, repeating this until the packet analysis means detects a new packet header,
And a recording device.

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