JPS6335343A - Data reception control method - Google Patents

Abstract

PURPOSE:To enable the reception data to be again read out, by a method wherein a page pointer indicating the address at which the page of the reception data in a reception buffer starts, even after execution of a first reading out, is provided. CONSTITUTION:A reception data is sequentially read out from an address 41 of a reception buffer 11 and transferred. When the reception data for one page content has been gathered in a page memory 12, a page pointer 31a is established to indicate the address 41. When the reception data in the page memory 12 is sent to a printer output circuit 14 and the page memory 12 becomes empty, the reception data is transferred from an address 42 pointed by a reading out pointer 33a to the page memory 12. When that for one page content has been transferred, a reading out pointer 33b indicates an address 43 and a page pointer 31b indicating the address 42 is established. The page for which the necessity of reading out again is gone, is set free as the area for allowing to write new reception data by erasing the page pointer indicating said page.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a data reception control method for receiving received data that may be stored in a receive buffer and read out again, such as received data of a laser printer. .

Receives the data sent to you, such as the printer
When printing according to that data, since the printing speed is slow, a receiving buffer is provided to receive and receive a large amount of data at once, and the data stored in the receiving buffer is read out in accordance with the printing speed. Therefore, a data reception control method is adopted in which a write pointer indicating an address to write data to a reception buffer and a successive pointer indicating an address from which data is read are provided.

(nS) With printers such as dot impact printers that do not require any processing after printing, printing can be completed by simply reading the data once.

However, in laser printers and the like, post-processing such as fixing is required after printing, and at this stage, the printed paper may become unusable due to a paper jam or the like. In that case, the same content must be printed again, but in the data reception control method using the write pointer and successive pointer described above, the data once read by the successive pointer is not stored. Since the area in the area has already been processed and is opened as a writing area, it is difficult to print the same content again.

The present invention was devised to solve the above problems.
It is an object of the present invention to provide a data reception control method that allows re-reading of received data.

In order to achieve the above-mentioned objective of making a first-hand prediction, the data reception control method of the present invention includes the steps of storing received data in a receiving buffer, and every time one page of stored received data is read. A step of setting a page pointer indicating the start address of the page, and a step of deleting the page pointer indicating the start address of this page when one page of received data indicated by the page pointer is not reread, and performing rereading. Sometimes, the method also includes a step of re-reading the received data whose start address is indicated by the page pointer.

The order in which page pointers are deleted follows the order in which they are set.

When rereading the valve plate, the received data is read from the address of the receive buffer indicated by the page pointer. On the other hand, if you increase the number of pages that enable re-reading of received data using page pointers, there will eventually be no area to write new received data to the receive buffer, so for pages that no longer need to be re-read, the page pointing to that page will be By deleting the pointer, the area is released for writing new received data.

Figure 3 is a block diagram showing the electrical configuration of a laser printer to which an embodiment of the present invention is applied.

An output 21 sent from a host computer or the like (not shown) is connected to the Centronics interface circuit 15.
is guided to the CPU 13 via. Receive buffer 1
1 has a size of 32 bytes that can store, for example, 15 pages of received data, and is connected to the CPU 13 so that it can exchange received data in both directions. In addition, a page memory 12 is provided as an area for temporarily storing one page of received data and organizing it for output.
The connection with 113 is bidirectional. The output from the CPU 13 is led to the printer output circuit 14.

The operation will be explained below.

Since the received data is sent via the Centronics interface circuit 15, the CPtJ 13 sequentially writes the received data into the reception buffer 11.

At the same time, the received data written in the receive buffer 11 is transferred to the page memory 12 until one page's worth of received data is completed. When the received data is complete, page memory 1
2, the received data is arranged in the order in which it will be printed, and then outputted to the printer output circuit 14 for printing.

The above laser printer is designed to print on the next sheet of paper while it is performing post-processing such as fixing the printed paper, and one sheet of paper that has already been printed is finished with the post-processing. When the paper is ejected, the printing of the two sheets has been completed and the paper is in the post-processing stage, and the received data from the third page later is being printed.

FIG. 1 is a diagram showing the relationship between a pointer and a reception buffer 11 showing an embodiment of the present invention.

Received data is written into the reception buffer 11 from right to left on the drawing, and is moved to the write pointer 32a.
indicates an address 51 for writing the next received data. The first readout is performed to transfer the received data to page memo January 2, and the readout position is indicated by the successive pointer 33. Received data is sequentially read from address 41 of receive buffer 11 and transferred, and when one page of received data is collected in page memory 12, page pointer 31a is set to indicate address 41. At this time, address 42
The received data up to now has been transferred to the page memory 12.

The received data in page memory 12 is sent to printer output circuit 1.
4 and the page memory 12 becomes empty, the page memory 12 is transferred from the address 42 pointed to by the successive pointer 33a.
When the received data is transferred, and one page has been transferred, the successive pointer 33b points to address 43, and the page pointer 31b points to address 42.

Similarly, page pointer 31C is set.

When the printed paper is being processed normally without a paper jam or the like, new received data is written to the receive buffer 11 by the write pointer 32b.
Received data from address 44 to address 45 is transferred to page memory 12 by successive pointer 33c. Then, the page pointer 31d is set, and
Since the received data printed on the paper 4 pages ago is not reread, the page pointer 31a is deleted in order to release the area from address 41 to address 42 where the received data is stored. .

Thereafter, the write pointer 32 and the successive pointer 33 move sequentially toward the left, and as a new page pointer 31 is set, the page pointers 31b and 31c are erased in the order in which they were set.

When the successive pointer 33e is transferring the received data at address 61 to the page memory 12, if the paper on which the received data between addresses 41 and 42 was printed becomes unusable due to a paper jam, etc., the jammed paper is first removed. After making preparations for new printing, such as this, the successive pointer 33e is moved to the address 41 indicated by the page pointer 31a, the received data is re-read from address 41, and the received data is transferred to the page memory 12. and print. Subsequently, the received data starting from address 42 is transferred and printed, and the process proceeds to the next page.

FIG. 2 is an explanatory diagram showing the relationship between the physical size of the reception buffer 11 and the logical address.

The receive buffer 11 is logically, that is, as an address for accessing the receive buffer 11, a buffer area that starts from 0 and continues indefinitely (infinitely large, within the range that may actually be used). is set as . However, as a method for realizing this, for example, a memory area having a physical size of 32 bytes is used. In the figure, the area is allocated to addresses 81 to 83. For addresses above address 83, the memory area starting from address 81 is allocated again. This means that writing received data to an address higher than address 83 also destroys the received data in the receive buffer 11 starting from address 81.

The size of the 32 bytes is large enough to store about 15 pages of received data, but the received data includes not only data for printing but also control data for instructing changes to the print position, etc. Since the received data for one page indicated by the page pointers 31e and 31f contains a lot of control data, etc., the size of normal received data that can store 10 pages or more is reduced to just 1 page. It is occupied by data for printing the page. Therefore, most of the memory area is occupied by the three pages of received data from page pointers 31e to 31h and the received data up to address 82 indicated by write pointer 32c, destroying the received data starting from page pointer 31e. Only area 72 and area 71 remain as areas where writing can be performed without any problems. The sum of the widths of area 71 and area 72 is, for example, 128 bytes, so if you write received data of 128 bytes or more, the received data starts from address 85 indicated by page pointer 31e and may be re-read. (This means that the reception of the received data has been stopped, and the write pointer 32c has stopped at address 82.)

On the other hand, the received data up to address 82 is read by the successive pointer 33f and transferred to the page memory 12, but the transferred received data is insufficient for one page. By the way, as for the received data that has been printed, the configuration is such that three pages' worth of received data is secured, so when the page memory 12 does not have one page's worth of received data, the page pointer 31e is not deleted. Remaining. That is, since the write pointer 32c cannot advance, it cannot receive the received data to be transferred to the page memory 12, and the successive pointer 33f cannot advance because there is no received data to transfer. Therefore, reception to the reception buffer 11, reception buffer 11
The system enters a halt state in which reading from and reading from is not performed.

To avoid this stopped state, receive new received data, and transfer one page worth of received data to page memo January 2, the page pointer 31e is deleted and the write pointer 32c is advanced. be able to do so. By this operation, address 81 is added to area 72.
Since the area including the size from address 84 to address 84 is opened to the write pointer 32c, received data is written to the receive buffer 11. Then, the received data up to address 86 is transferred to the page memo 1J12 by the successive pointer 33g. At this time, if the page memory 12 does not yet have one page worth of received data, the page pointer 31f is deleted. Furthermore, if necessary, the page pointer 31g is deleted. If the received data transferred to the page memory 12 contains a lot of control data, etc., and one page of received data is not collected in page memo January 2, regardless of the deletion of the page pointer 31g, the page pointer 31h is deleted and the page The area 74 is made smaller, for example, by 128 bytes, and the 128 bytes are released for the write pointer 32 until one page of received data is stored in the memory 12.

Note that the present invention is not limited to the above-mentioned embodiments, and the page pointer to be deleted can be changed even when the received data to be reread is for four or more pages, or for less than two pages. It is possible to pass it by.

The data reception control method of the present invention provides a page pointer indicating the starting address of the page of received data in the reception buffer even after the first reading, so that the data reception control method re-reads the received data. It becomes possible to provide a data reception control method that allows

[Brief explanation of drawings]

FIG. 1 is a diagram showing the relationship between a pointer and a reception buffer 11 showing an embodiment of the present invention, and FIG. 2 is an explanatory diagram showing the relationship between the physical size of the reception buffer 11 and a logical address.
FIG. 3 is a block diagram showing the electrical configuration of a laser printer to which an embodiment of the present invention is applied. 11...Reception buffer, 31...Page pointer, 32...Write pointer, 33...Continuation pointer.

Claims (1)

[Claims] (1) In a data reception control method for receiving received data that is stored in a reception buffer and may be read out again after being read out for the first time, the step of storing the received data in the reception buffer; a step of setting a page pointer indicating the start address of the page each time one page of the stored received data is read; and when the one page of the received data indicated by the page pointer is not read out again, this page is the step of deleting the page pointer indicating the start address of the page pointer; and the step of re-reading the received data whose start address is indicated by the page pointer when rereading, the page pointer to be deleted is a data reception control method characterized in that data is deleted according to a set order.