JPH09160823A - Area managing and controlling device for memory in electronic equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To retrieve an usable free area at a high speed in managing and controlling of the plural areas of a memory which is provided in an electronic equipment. SOLUTION: In a free area managing table memory 25b, area size data, a free area head address and a free area table where the head address of the preceding free area being adjacent to the precedent side and the head address of the succeeding free area being adjacent to the following side are made into a table are stored at every area concerning the free area which is not under usage within the plural areas of a work memory 25c. Then, at the time of necessity for using the memory, the free area table is retrieved at first, the free area of a requested area size YS is searched at a high speed and, after that, the free area managing table memory 25b and a whole area managing table memory 25a are updated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an area management control apparatus for a memory provided in an electronic device such as a printer or a facsimile machine, and more particularly to a free area for managing an empty area of all areas to be managed by the memory. The present invention relates to a method for speeding up the search speed of an empty area by searching the area management table.

[0002]

2. Description of the Related Art Conventionally, various printers such as a laser printer are connected to a host computer such as a large computer or a personal computer, receive image data or text data transmitted from the host computer, and receive the image data or the image data. The text data is expanded into dot pattern data, and the dot pattern data is printed on the printing paper. By the way, in general, a RAM composed of a volatile memory is provided in the control device of the printer.
In the AM, not only the image data sent from the host computer but also the font data for character printing are stored, and the dot image data expanded into printable dot pattern data based on the print data is also stored. It has become.

In this case, various data received from the host computer and the expanded dot image data are stored in the R
In many cases, storage control is performed so that the data is continuously stored in a predetermined data storage area assigned to the AM. Here, in general, this data storage area is used as an area to be managed, and area size data for each area, identification data indicating whether the area is in use, and a start address for identifying the area are tabulated. An all area management table is provided separately.

At the time of writing data, first, the presence or absence of a writable free area in the data storage area is searched for. In that case, based on the data in the total area management table, the area in use and Including the empty area, the usage status of whether or not it is in use is searched for each area from the top area, and when it is empty, the area size of the empty area is obtained and it is determined whether or not it is writable. That is, these series of search controls are sequentially executed, and when a writable free area is detected, a new area for writing data is secured in the data storage area, and
The corresponding data in the all area management table is updated, and the new area is also registered in the all area management table as "in use". On the other hand, unnecessary data is erased from the data storage area, and the area occupied by the erased data is registered in the all area management table as an "empty area". There is.

[0005]

As described above, a writable empty area for writing various data received from the host computer and expanded dot image data into a predetermined data storage area assigned to the RAM. At the time of searching, based on the data of the all area management table, the usage status is searched from the top area for each area including the "in use" area, and when the area is empty,
Since a series of these search controls are performed in order to determine the area size of the free area and determine whether it is writable, the number of search target areas including the "in use" area is large. Therefore, there is a problem that the search control of the free area is prolonged. In particular, when the memory capacity of the data storage area is large and a free area is provided on the end side of the data storage area, the number of search target areas becomes very large, and the search control requires several seconds to several tens of seconds. Will be required.

An object of the present invention is to provide an area of a memory in an electronic device that can speed up search control of a data writable empty area in management control of a plurality of areas included in a memory provided in the electronic device. It is to provide a management control device.

[0007]

According to a first aspect of the present invention, there is provided a memory area management control device in an electronic device, which is a memory area management control device in an electronic device such as a printer or a facsimile machine. In an area management control device that manages a plurality of areas in a memory having areas, the area size data, the identification data indicating whether or not the area is in use, and the area specifying 1 for all the areas to be managed. Or, an all area management table in which data of a plurality of start addresses is tabulated, and an all area management table update for updating the corresponding data of the all area management table according to the change of the area size or the usage status of any area Means and one or a plurality of area size data and area specifying data for each area for a free area which is not used among the areas to be managed. A free area management table in which the data of the head address is tabulated, and a free area management table updating means for updating the corresponding data of the free area management table according to the change of the area size or the usage status of any free area. It is equipped with.

To explain the operation, the all area management table shows, for all areas to be managed, area size data, identification data indicating whether or not the area is in use, and one or a plurality of areas specifying areas. The data of the head address is stored as a table, and in the free area management table, the area size data and the area specifying data 1 or The data of multiple start addresses is stored as a table and stored, so the free area where data can be written can be used by searching the data in the free area management table based on the area size required for writing. It is possible to easily and quickly find only the empty area excluding the inner area.

Then, since the data is written and used in the empty area, the all area management table updating means corresponds to the all area management table according to the change of the area size or the usage status of any area. The free area management table updating means updates the corresponding data in the free area management table in accordance with the change of the area size or the usage status of any free area. That is, by separately providing a free area management table for a free area that is not in use among the areas to be managed, the data in the free area management table is searched to perform a search process of a writable free area of data. The area securing process can be simplified and speeded up. Further, the data of the free area management table and the entire area management table can be updated for the next free area search.

According to a second aspect of the present invention, there is provided an area management control device for a memory in an electronic device according to the first aspect of the invention, wherein one or a plurality of head addresses for area specification in the all area management table are the head addresses of the respective areas. , The start address of the front area adjacent to the preceding side and the start address of the rear area adjacent to the subsequent side. Explaining the operation, the same operation as in claim 1 is achieved, but one or a plurality of start addresses for specifying the area in the entire area management table are the start address of each area and the start address of the previous area adjacent to the preceding side. And the start address of the rear area adjacent to the succeeding side are included. Therefore, when updating the data, the area to be updated is searched based on the start address of the front area and the start address of the rear area. Can be simplified and the update processing of the corresponding data can be speeded up.

According to a third aspect of the present invention, there is provided an area management control device for a memory in an electronic device according to the first or second aspect of the present invention, wherein one or a plurality of start addresses for area identification in the free area management table are free areas. The start address of the area and the start address of the previous empty area adjacent to the leading side,
This includes the head address of the rear empty area adjacent to the subsequent side. Explaining the operation, the same operation as that of claim 1 or claim 2 is achieved, but one or a plurality of start addresses for specifying an area in the free area management table are adjacent to the start address of each free area on the leading side. Since the start address of the front empty area and the start address of the post empty area adjacent to the subsequent side are included, when updating the data, the start address of the front empty area and the start address of the post empty area are used. Thus, the search for the area for updating is simplified, and the update processing of the corresponding data can be speeded up.

According to a fourth aspect of the present invention, there is provided a memory area management control device in an electronic apparatus, wherein the memory is a volatile memory installed in a printer. The operation is the same as that of claim 3, but when writing the received data or the expanded dot image data to the volatile memory equipped in the printer, a writable space for these data is available. Area search control can be speeded up.

According to a fifth aspect of the present invention, there is provided a memory area management control device in an electronic apparatus, wherein the memory is a volatile memory equipped in a facsimile machine. The operation is the same as that of claim 3, but when the received data is written in the volatile memory provided in the facsimile, the search control of the writable empty area of the data is performed at high speed. Can be converted.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. In the present embodiment, image data such as text data and graphics is received from an external device, and for image data, the print data is printed by a printing mechanism, and for text data, contour line data representing a contour of a character ( This is a case where the present invention is applied to a laser printer that creates and prints dot pattern print data by converting outline data) into dot data for each pixel for printing. Laser printer LP
Briefly, as shown in FIG. 1, it is basically composed of a control unit 10, a dot data creation device 20, and a printing mechanism 30.

The control unit 10 of the laser printer LP is equipped with a serial interface for receiving various data supplied from the external device 50, a video controller, a DC controller, etc., and the dots of the character created by the dot data creating device 20. The pattern data and the image data are printed on a print sheet by driving and controlling a laser diode, a polyhedral mirror, a developing mechanism and a fixing mechanism, which are light emitting elements of a semiconductor laser provided in the printing mechanism 30. The control unit 10 is the same as the one generally used and is not directly related to the present invention, and thus its detailed description is omitted.

As shown in FIG. 2, the dot data producing device 20 basically has a CPU 21 and a CPU 21.
1 is composed of an operation panel 22, which is connected via a bus 26 such as a data bus, ROMs 23 to 24, and a RAM 25.
Connected to the bus inside. In the font data memory 23 including the ROM, contour line data regarding each of a plurality of characters such as characters, symbols and numbers is stored in association with a character code. In addition, the program memory 24, which is a ROM, includes dot data creation control for creating dot data for printing from the received image data or text data, and includes the laser printer L.
Various control programs for controlling the driving of P, and a control program for area management control peculiar to the present invention described later are stored.

The RAM 25, which is a volatile memory, is provided with an entire area management table memory 25a, a free area management table memory 25b, a work memory 25c, and various other buffers and memories. As shown in FIG. 3, the work memory (corresponding to a memory having a plurality of areas having variable area sizes) 25c has a predetermined memory capacity (address "1999") from a predetermined start address (eg, "1000"). Up to), and the work memory 25c stores the received text data, image data, font data, expanded dot image data, or the like in an area secured according to the data amount. . Here, in the work memory 25c, as shown in FIG. 3, the area in use is illustrated by hatching, and three empty areas (first to third empty areas) are present.

All area management table memory 2 of RAM 25
In 5a, as shown in FIG. 4, for all areas to be managed in the work memory 25c, area size data for each area, the start address of each area, and the start of the previous area adjacent to the preceding side An all-area management table in which an address, a head address of a rear area adjacent to the subsequent side, and identification data (“in use” or “empty”) whether or not in use is stored is stored. That is, the start address is
"1100", "1200", "1300", "1400", "1500",
Area management data regarding eight areas “1600”, “1800”, and “1900” are stored in a table. Here, the symbol "-" means that it does not exist or is indefinite.

Further, in the free space management table memory 25b of the RAM 25, as shown in FIG. 5, for the free space which is not in use among the plurality of regions of the work memory 25c, the data of the area size for each area is stored. And a free area management table in which a start address of a free area, a start address of a front free area adjacent to the leading side, and a start address of a rear free area adjacent to a subsequent side are stored. That is, as shown in FIG. 3, in the area use condition in which the first to third free areas are present, the area management control described later is executed to determine the address "13" as the first free area.
The area size is "100 bytes" from 00 ", and the area size is" 200 bytes "from the address" 1600 "as the second free area.
As the third free area, the area size "100 bytes" from the address "1900" is already stored. Here, the symbol "-" means that it does not exist or is indefinite.

Next, the routine of the area management control executed by the dot data creation device 20 of the laser printer LP will be described with reference to the flowchart of FIG. still,
Reference numeral Si (i = 10, 11, 12, ...) In the drawing represents each step. This control is started when an empty area to temporarily store is needed to write various received data or to write expanded dot image data. The size YS is read (S10), and the first free area is searched based on the data in the free area management table memory 25b (S11).

Next, when the area size RS of the first empty area read from the empty area management table is smaller than the requested area size YS (S12: No), the next empty area on the subsequent side is searched (S13). ), When the empty area exists (S14: Yes), S12 to S14 are repeatedly executed. When the area size RS is equal to or larger than the requested area size YS (S12: Yes), the area having the area size YS can be secured, so that the area is secured by the start address of the empty area and the area size (S16). ).

For example, if the requested area size YS is "15"
When it is "0 bytes", it is possible to secure the area in the second free area whose start address is "1600" and the area size is "200 bytes" in FIGS.
As indicated by the reverse slash, the start address of the empty area is "16
A new area with an area size of "150 bytes" is newly allocated from "00". Next, an update process for updating the corresponding data in the all area management table is executed (S17). For example, as shown in FIG. 8, regarding the area having the start address of “1600”, the area size is updated to “150”, the start address of the rear area is updated to “1750”, and the identification data is updated to “in use”. At the same time, the start address of the previous area is updated to “1750” for the area having the next start address of “1800”. Here, this S17 corresponds to the all area management table updating means.

Next, an updating process for updating the corresponding data in the free space management table is executed (S18), the control is terminated, and the process returns to the main routine. For example,
As shown in FIG. 9, the start address of the free area is updated to “1750” and the area size is changed to “50” for the second free area, and the start address of the previous free area is updated for the next third free area. Is updated to "1750". Here, this S18 corresponds to the free space management table updating means. By the way, when an area larger than the requested area size YS cannot be secured (S12: No, S13, S14: No), error processing such as setting an error flag is executed (S15), and this control is ended. And then return.

Next, the operation of the area management control will be described. In the all area management table memory 25a, for all areas to be managed in the work memory 25c, area size data for each area, identification data indicating whether or not the area is in use, and area identification for area identification. A full area management table is stored in which the start address, the start address of the front area adjacent to the preceding side, and the start address of the rear area adjacent to the subsequent side are tabulated, and the free area management table memory 25b stores the work memory 25c. For the empty areas that are not in use among the plurality of areas, the area size data for each area, and the start address of the empty area and the start address of the previous empty area that is adjacent to the leading side for specifying the area A free area management table in which the head address of the rear free area adjacent to the side is tabulated is stored.

That is, regarding the writable free area of data, the data in the free area management table is searched based on the area size YS required for writing, and only the free area excluding the used area is searched. As a result of searching, it is possible to simplify and speed up the process of searching for a writable free area of data and the process of securing the area. Then, since the data is written and used in the free area, the corresponding data in the all area management table is updated according to the change of the area size and the usage status for the next free area search. The corresponding data in the free area management table is updated according to the change in area size or usage of the free area.

Thus, in addition to the all area management table for all areas to be managed in the work memory 25c,
Since the free area management table for the free area which is not used in the area of the work memory 25c is provided, the free area in which the data can be written is searched for the free area management table to find the used area. It is possible to simplify and speed up the process of searching for a writable free area of data and the area securing process for only the removed free area. Further, the data of the free area management table and the entire area management table can be updated for the next free area search.

Further, in the all area management table, the head address of each area, the head address of the front area adjacent to the leading side, and the head address of the rear area adjacent to the trailing side are stored in order to specify the area. Therefore, when updating the data,
Based on the start address of the front area and the start address of the rear area, the search for the area to be updated can be simplified, and the update processing of the corresponding data can be speeded up. Further, the free area management table stores the start address of the free area, the start address of the previous free area adjacent to the preceding side, and the start address of the post free area adjacent to the subsequent side for the area identification. Therefore, when updating the data, the search for the area to be updated is simplified based on the start address of the previous empty area and the start address of the post empty area, and the update processing of the corresponding data is performed at high speed. Can be converted.

By the way, when the free space management table is created and stored in the RAM which is a volatile memory provided in the control device of the facsimile machine, this R
For example, when writing the received data to the AM, by searching this free area management table, it is possible to speed up the search control of the writable free area of the data.

The data of the entire area management table and the free area management table provided in the RAM 25 are stored in the work memory 25.
Based on the existing technology or the technology obvious to those skilled in the art regarding the above-described embodiment, the table is configured to be provided on the head side of c, or both tables are configured to store only the head address of the area. Various changes may be made.
Further, it is needless to say that the present invention can be applied to a memory area management control device in electronic equipment such as various printers and facsimile devices.

[0030]

According to the area management control device for a memory in an electronic device according to a first aspect of the present invention, in an area management control device for managing a plurality of areas in a memory having a plurality of areas of variable area size, An all area management table for all areas, an all area management table updating means, a free area management table for empty areas that are not used among the areas to be managed, and a free area management table updating means are provided to write data. The available free space,
By searching the data in this free space management table,
Since only the free area excluding the area in use is searched, it is possible to simplify and speed up the search processing of the writable free area and the area securing processing. Further, the data of the free area management table and the entire area management table can be updated for the next free area search.

According to the area management control device of the memory in the electronic device of the second aspect, the same effect as that of the first aspect can be obtained, but one or a plurality of head addresses for area identification in the entire area management table are It includes the start address of the area, the start address of the previous area adjacent to the leading side, and the start address of the back area adjacent to the following side. It is possible to speed up the update processing of the corresponding data based on the area start address.

According to the area management control device of the memory in the electronic device of the third aspect, the same effect as that of the first or second aspect is obtained, but one or a plurality of heads for area identification in the free area management table are provided. Since the address includes the start address of each free space, the start address of the front free space adjacent to the leading side, and the start address of the rear free space adjacent to the succeeding side, when updating the data, these Based on the start address of the front empty area and the start address of the rear empty area, it is possible to speed up the update processing of the corresponding data.

According to the memory area management control device in the electronic device of the fourth aspect, the same effect as that of the third aspect can be obtained, but the received data and the expanded data are stored in the volatile memory equipped in the printer. When writing dot image data, it is possible to speed up search control of a writable free area of these data. According to the area management control device of the memory in the electronic device of the fifth aspect, the same effect as that of the third aspect can be obtained, but, for example, when the received data is written in the volatile memory equipped in the facsimile apparatus, It is possible to speed up the search control of the writable free area of this data.

[Brief description of the drawings]

FIG. 1 is a block diagram of a control system of a laser printer according to an embodiment of the present invention.

FIG. 2 is a block diagram of a control system of a dot data creation device of a laser printer.

FIG. 3 is an explanatory diagram illustrating an in-use area and a free area in a work memory.

FIG. 4 is an explanatory diagram illustrating a data configuration of an entire area management table.

FIG. 5 is an explanatory diagram illustrating a data structure of a free area management table.

FIG. 6 is a schematic flowchart of a routine for area management control.

FIG. 7 is a view corresponding to FIG. 3 in which a new area is secured.

FIG. 8 is a view corresponding to FIG. 4 updated according to a change in area.

FIG. 9 is a diagram corresponding to FIG. 5, which is updated according to a change in free space.

[Explanation of symbols]

 LP laser printer 21 CPU 24 ROM (program memory) 25 RAM 25a All area management table memory 25b Free area management table memory 25c Work memory

Claims (5)

[Claims] 1. An area management control device for a memory in an electronic device such as a printer or a facsimile machine, which manages a plurality of areas in a memory having a plurality of areas of variable area size, A total area management table that tabulates, for each area, area size data, identification data indicating whether or not in use, and one or more head address data for area identification, Depending on the area size and usage status of the
All area management table updating means for updating the corresponding data in the all area management table, and area size data and area identification data 1 for each area for the unused areas of the areas to be managed
Alternatively, a free area management table in which data of a plurality of start addresses is tabulated, and a free area management table for updating the corresponding data of the free area management table according to the change of the area size or the usage status of any free area An area management control device for a memory in an electronic device, comprising: an updating unit. 2. One or a plurality of head addresses for area specification in the all area management table include a head address of each area, a head address of a front area adjacent to the leading side, and a back area adjacent to the trailing side. The area management control device for a memory in an electronic device according to claim 1, further comprising a head address. 3. The one or more start addresses for specifying the area in the free area management table are the start address of each free area, the start address of the previous free area adjacent to the leading side, and the back address adjacent to the succeeding side. An area management control device for a memory in an electronic device according to claim 1 or 2, further comprising a start address of an empty area. 4. The memory area management control device in an electronic apparatus according to claim 3, wherein the memory is a volatile memory equipped in a printer. 5. The memory area management control device in an electronic apparatus according to claim 3, wherein the memory is a volatile memory installed in a facsimile apparatus.