KR20000004317A - Method of reading and writing an interleaved image data at a dynamic ram at a pdp television - Google Patents

Abstract

PURPOSE: A method of reading and writing an interleaved image data at a dynamic RAM at a PDP television is provided to enable the circuit to be stable. CONSTITUTION: An image data of a first vertical line is stored at {MSB column region, M-1 column region, M-2 column region,..., M-6 column region, LSB column region} of the first row. An image data of a second vertical line is stored at {MSB column region, M-1 column region, M-2 column region,..., M-6 column region, LSB column region} of the second row. An image data of 480th vertical line is stored at {MSB column region, M-1 column region, M-2 column region,..., M-6 column region, LSB column region} of the 480th row. The stored data is sequentially read with sub-frame.

Description

Method of writing and reading interlaced video data to and from a dynamic random access memory in a plasma display panel television

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display television (PDP-TV), and to a method of recording and reading in a dynamic RAM after inputting digital data sampled with 8 bits and rearranging the data to be suitable for a PDP system.

As an image display method of a television, a cathode ray tube (CRT) currently used employs a method in which an electron gun sequentially scans pixel by pixel, and a gray scale is formed as a simple driving circuit driven by an analog system. Such CRTs are very fast with several tens of nanoseconds (ns), but it is very difficult to implement the driving of millions of pixels by one pixel when the number of pixels increases to several million, such as a high-definition television.

Meanwhile, a plasma display panel (PDP), which is recently attracting attention as a next-generation flat panel display, is an apparatus that displays an image by using light generated from plasma formed by gas discharge. It is possible to produce TV and is thinner and lighter than conventional TV, so it is the closest device to wall-mounted display. In other words, plasma refers to a state in which a substance in a gaseous state is ionized by receiving energy from an external force such as a voltage, and a plasma display uses a glow discharge region to display text, graphics, or images in a gas discharge phenomenon. Say.

The PDP has a basic property which is very suitable for large size, firstly, the PDP has a structure in which two sheets of glass are bonded at intervals of several hundred μm or less to fill gas. Therefore, the thickness is as thin as about one tenth of the cathode ray tube (CRT), and the weight can be reduced to about one sixth of the CRT.

Second, PDP drives the panel by using the Marx Driving method using the excellent nonlinearity characteristics of gas discharge. Here, nonlinearity is because the gas discharge phenomenon is caused by ionization of gas. Discharge occurs only when a voltage equal to or higher than the discharge voltage at which such an ionization reaction can occur sufficiently is a characteristic of gas discharge in which discharge does not occur at a voltage below that. Therefore, a large area panel drive is very easy because a plurality of pixels can be selectively driven without an auxiliary device by simply selecting a matrix type electrode array and selecting a gas suitable for discharge.

Third, it has a memory function, which can be referred to as a discharge memory function, whereby the discharged and non-discharged cells operate at different discharge voltages. Therefore, when the cell to be displayed is selected by the pre-discharge, the post discharge is determined by the pre-discharge. In particular, in AC PDP, the generated charge is accumulated and stored on the surface of the dielectric, so that discharge memory of a very long time is possible, and thus driving of a video is very easy.

Fourth, the wide viewing angle is wide. PDP is a self-luminous display element, and since the reflection to the partition further widens the viewing angle, a panel having a wide viewing angle of 160 degrees or more can be manufactured. Fifth, since the plasma formed by the gas discharge affects the display characteristics of the panel, even if the outside temperature changes from minus 100 ° C to the image 100 ° C, the operating characteristics of the panel do not change, and the distortion characteristics due to the magnetic field do not exist in the PDP. Does not appear

The PDP having the above characteristics is an active light emitting device in which ultraviolet rays generated from gas discharge excite a fluorescent film to implement an image. That is, since the PDP uses ultraviolet light emission by gas discharge as a light source corresponding to each pixel, the driving circuit simply functions to form or erase gas discharge for each pixel in order to implement a display image. The driving circuit includes an image signal and a signal control unit for each pixel constituting an image, and a high speed high voltage switching control unit capable of forming or erasing ultraviolet rays generated from each pixel. The driving sequence of the driving circuit of the PDP can be classified into three types: selection operation, holding operation, and erasing operation. Hereinafter, the three operations will be briefly described as follows.

The selection operation described above is a driving operation necessary for initial discharge formation. In the case of the Pen + mixture of He + Xe and Ne + Xe commonly used in the PDP, a potential of 240 V to 280 V is applied. In the case of AC PDP, a third electrode is introduced to reduce the high current caused by the sustain electrode in the surface discharge form and the parasitic capacitor caused by the dielectric, and adopt a driving method that separates the selection operation from the sustain operation.

The holding operation is a driving operation in which the discharge is held by a holding pulse of a voltage lower than the selection pulse using the memory function characteristic of the gas discharge. In the case of AC PDP, the memory function effect by wall charge is used, and in the case of DC PDP, the self-priming particle supply effect is used. As described above, in the case of the memory driving method which can separate the selection operation and the holding operation by using the memory function, the PDP operates without degrading the luminance even for a large display element in the case of high gradation display for realizing a high quality display element. It provides a driving method that can be done. In the case of AC PDP, in the period of neutralizing the wall charge, the discharge is formed at a low voltage so that the wall charge is not sufficiently formed, or the wall charge is prevented from reaching the steady state due to the erase pulse having a short pulse width. Remove

AC PDPs have a unique memory function because charged particles such as electrons and ions formed in gas discharge form wall charges in the dielectric covering the electrode. That is, there is no wall charge in the dielectric when there is no discharge, and wall charges are accumulated on the dielectric when a discharge is formed. When the wall charges are present, the potentials applied to the external electrodes and the potentials due to the wall charges are added together, so that a discharge is formed at a low voltage. Thus, it is possible to separate the operation of causing discharge at low potential with the help of addressing and discharging without the help of wall charge.

In order to display the image on the PDP by the above-described driving method, the digitized image data is stored in the memory unit after the data is rearranged in a form suitable for PDP gray level processing. The way video signals are stored in memory depends on the type of memory. The types of memory include dynamic RAM (DRAM), static RAM (SRAM) and synchronous dynamic DRAM (Synchronous DRAM). There is a need for a method of recording and reading video signals to RAM.

Accordingly, the present invention has been made to meet the above-mentioned necessity. In the case of storing a video signal using dynamic RAM as a frame memory in a PDTV, the NTSC video signal received in an interlaced manner is recorded in the dynamic RAM. The purpose is to provide a way to read.

In the PDTV television of the present invention for achieving the above object, a method of recording interlaced video data into a dynamic RAM includes sampling a complex video signal of an interlaced scan method and classifying the dynamic RAM into a weight by PISO unit. A method of writing to a frame memory for use, comprising: a first step of dividing a dynamic RAM into an odd field storage column region and an even field storage column region; The dynamic RAM is divided into MSB weight storage row zone, M-1 weight storage row zone, M-2 weight storage row zone,. A second step of dividing the M-6 weight storage row region and the LSB weight storage row region; When odd field image data is input, the first to eighth sampled image data of the first line of the odd field is displayed in the first column of the first column in the first column {rows 1 MSB, first M-1, ...]. , 1M-6 rows, 1 LSB rows}, and the 9-16th sampled image data of the first line is stored as {second MSB row, 2M-1 rows,... , Rows 2M-6 and 2LSB}, respectively, and the image data of the first line of the odd field is stored in the {MSB row area, the first column of the odd field storage column area by repeating the above process. Area M-1,… A third step of storing the respective weights in the M-6 region and the LSB region; The third process is repeated for the second to the 240th lines of the odd field, so that the image data of the second line is stored in the {MSB area, M-1 area,. , Section M-6, section LSB}, by weight, The image data of the 240th line is the {MSB line, M-1 line,. A fourth step of storing the respective weights in the M-6 region and the LSB region; When even field image data is input, the first to eighth sampled image data of the first line of the even field is selected from the {first MSB row, first M-1 row,. , 1M-6 rows, 1 LSB rows}, and the 9-16th sampled image data of the first line is stored as {second MSB row, 2M-1 rows,... , Rows 2M-6 and 2LSB}, respectively, by weight, and repeating the above process to store the image data of the first line of the even field in the {MSB row area, the first column of the even field storage column area; Area M-1,… A fifth step of storing the respective weights in the M-6 region and the LSB region; And repeating the third process with respect to the second to the 240th lines of the even field, and reconstructing the image data of the second line into the {MSB row area, M-1 row area,. , Section M-6, section LSB}, by weight, The image data of the 240th line is the {MSB line, M-1 line,. , M-6, and LSB, each of which comprises a sixth process of storing each weight.

In the method of reading interlaced image data from the dynamic RAM in the PDTV television according to the present invention, the sampled image data of the odd field is recorded by weight and by each line in the odd field storage column area, and for even field storage. In the column section, in a method of reading image data of one frame for each subframe from the dynamic RAM in which even-field sampled image data is recorded for each weight and for each line, the MSB row of the first column in the column field for odd field storage. A first step of sequentially reading the data stored in the zone to read all the MSB weight data of the first line; A second step of jumping to an even-field storage column region and sequentially reading data stored in the MSB row region of the first column to read all the MSB weight data of the second line; Jump to the odd field storage column section to read MSB weight data of the third line from the MSB row section of the second row, jump to the even field storage column section and jump to the MSB row section of the fourth line from the MSB row section of the second column. The weight data is read, and the above process is repeated to read the MSB weight data of an odd number of lines from the MSB row section of the odd field storage column section, and from the MSB row section of the even field storage column section. A third step of reading MSB weight data of even lines for one frame; And reading M-1 weight data of odd lines for one frame from row M-1 of the odd field storage thermal zone in the same manner as steps 1 to 3, and reading the even field storage thermal zone. Reads M-1 weight data of even lines for one frame from M-1 row area, and reads all M-1 weight data for one frame. And read odd-line LSB weight data of one frame from the LSB row section of the odd-field storage column section, and read LSB-weight data of even lines of one frame from the LSB row section of the even-field storage column section. And a fourth process of reading all the LSB weight data for one frame.

1 is a block diagram showing the configuration of a general all AC PDP-TV system;

FIG. 2 is a block diagram illustrating a configuration of a memory unit in FIG. 1;

3 is a state diagram showing a data format of the sampled video data sorted by an 8-bit PISO stage;

4 is a memory map of a frame memory using dynamic RAM for storing 8-bit data according to the present invention.

Explanation of symbols on the main parts of the drawings

112: antenna 114: AV part

116: ADC section 118: Memory section

120: data interface unit 122: timing controller unit

124: AC-DC converter 126: high voltage drive circuit

128: scan / hold driver IC 130,132: address driver IC

134: PDP panel 210: data rearrangement

211: first PISO unit 212: second PISO unit

213: D flip flop and multiplexer 214: first tri-state buffer

215: second tri-state buffer 220: address generator

221: recording address generator 222: poison address generator

223: address selector 230: first frame memory

240: second frame memory 250: data selector

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Figure 1 shows the entire AC type PDP-TV system according to the present invention, the AV unit 114 receives the NTSC composite video signal through the antenna 112, horizontal and vertical synchronization with analog R, G, B The synchronous signal is separated, an average picture level (APL) corresponding to the average value of the brightness signal (Y) is obtained, and provided to the ADC unit 116. The NTSC composite video signal is composed of two fields of Odd / Even in an interlaced scanning method.

The ADC unit 116 receives analog R, G, and B signals as inputs, converts them into digital data, and outputs the digital data to the memory unit 118, where the digital data is converted into image data in order to improve the brightness of the PDP-TV system. to be. The ADC unit 116 is largely divided into an amplifier, a clock generator, a sampling area setting unit, and a data mapping unit.

The memory unit 118 reconstructs image data of one field into a plurality of subfields for grayscale processing of the PDP, and then rearranges the most significant bit (MSB) to the least significant bit (LSB). As shown in FIG. 2, the memory unit 118 includes a data rearranger 210, an address generator 220, a control clock generator (not shown), and first and second frame memories 230 and 240. And a data selector 250.

Referring to FIG. 2, the data rearrangement unit 210 includes two parallel input serial output (PISO) units 211 and 212, a D flip flop and a multiplexer 213, and two tri-state buffers 214 and 215. The image data provided in parallel (MSB to LSB) in the unit 116 is rearranged so as to store bits having the same weight (weight) in one address of the two frame memories 230 and 240.

That is, the first PISO unit 211 and the second PISO unit 212 alternately repeat the load operation and the shift operation to classify the sampled image data by weight, and the eight image data in which the first PISO unit 211 is sampled. During loading, the second PISO unit 212 outputs eight image data previously loaded while sequentially shifting from the most significant bit MSB to the least significant bit LSB. In addition, while the first PISO unit 211 outputs the image data loaded by the weight by shifting, the second PISO unit 212 loads the eight sampled image data again.

The D flip flop and the multiplexer 213 selects the same weighted data output in the shift mode among the first PISO unit 211 and the second PISO unit 212 and supplies them to two tri-state buffers 214 and 215. The two tri-state buffers 214 and 215 connect rearranged image data provided from the D flip flop and the multiplexer 213 to the frame memories 230 and 240 operating in the recording mode.

In general, in the case of a PDP TV having an aspect ratio of 16 to 9, the capacity of the frame memories 230 and 240 capable of storing image data of one frame may be obtained as in Equation 1.

853 × 3 (R, G, B) × 480 × 8bit ≅ 10Mbit

That is, two frame memories 230 and 240 of 10 Mbit capacity are used to alternately perform writing and reading operations in units of frames.

The address generator 220 of FIG. 2 is divided into a write address generator 221 and a read address generator 222. The address generator 220 generates an address of data stored in one frame memory 230 and 240 and provides the address to the frame memory 230 and 240. do. In order to process the PDP gray level, the subfields are divided by weight of all image data constituting one frame, and when reading, the image data corresponding to each frame must be read in sequence and provided as a data interface. The read address generators 222 are very different from each other. The address selector 223 provides a corresponding address to the first and second frame memories 230 and 240 according to each operation mode of the first frame memory 230 and the second frame memory 240, that is, a write mode or a read mode. Do it.

The data selector 250 selects image data output from the frame memory operating in the read mode among the first and second frame memories 230 and 240 and provides the image data to the data interface unit 120.

The data interface unit 120 of FIG. 1 temporarily stores R, G, and B data supplied from the memory unit 118 and provides the data in the form of data required by the address driver ICs 130 and 132. That is, the R, G, and B data output from the memory unit 118 should be rearranged and supplied to the address driver ICs 130 and 132 according to the RGB pixel arrangement of the panel 134. A space for temporarily storing data of line amount (640 lines x 3 (R, G, B) x 2 = 3840 bits) is required. While inputting one line of data, the operation of outputting the data of another line is alternated. To perform.

The high voltage driving circuit unit 126 combines the DC high voltage supplied from the AC-DC converter 124 according to the control pulses of various logic levels output from the timing controller unit 122 to the scan / maintenance driving IC 128. The control pulse required may be generated to drive the PDP panel 134. In addition, the data stream provided from the data interface unit 120 to the address driver ICs 130 and 132 is also raised to an appropriate high voltage level to enable selective recording on the panel.

FIG. 3 shows a format of data sorted into 8-bit PISO units. That is, the data of D0 is an MSB of 8-bit image data sampled 1 to 8 times, D1 is M-1 of 8-bit image data sampled 1 to 8 times, and D2 is M of 8-bit image data sampled 1 to 8 times. -2, … , D7 denotes an LSB of 8-bit image data sampled from 1 to 8 times, and D8 denotes an MSB of 8-bit image data sampled from 9 to 16 times. Denotes the LSB of 8-bit image data sampled at the 9th to 16th times.

On the other hand, since the PDP system displays one frame of image data by weight, the following amount of frame memory is required.

That is, in 640x480 mode, 640x480x8bit = 2,457,600bits of memory is required per channel (e.g. R channel), and 640 ÷ 8 = 80 times of addressing per line in 8bit processing. Do. In the wide mode 853x480 mode, 853x480x8bit = 3,275,520bits of memory per channel is required, and 853 ÷ 8 ≒ 107 addressing per line is needed for 8bit processing.

FIG. 4 shows a memory map of a frame memory using dynamic RAM for storing 8-bit image data sorted by weight from the first and second PISO units. The dynamic RAM stores an odd field for storing odd field image data. It is divided into a heat zone for even field storage and an even field for storing even field image data. In addition, the dynamic RAM includes an MSB row area for storing MSB weight data, an M-1 row area for storing M-1 weight data, an M-2 row area for storing M-2 weight data, … It is divided into the M-6 row area for storing M-6 weight data and the LSB row area for storing LSB weight data.

In general, NTSC video signals are input by interlaced scanning. Odd field video signals are sampled and classified by weight. MSB weight data is stored in the MSB row area of the odd field storage column, and M-1 weight data is odd. M-2 weight data is stored in the M-2 row area of the odd field storage thermal zone,... For example, M-6 weight data is stored in the row M-6 of the odd-field storage column, and LSB weight data is stored in the LSB row of the odd-field storage column.

Further, even field video signals are sampled and classified by weight, so that MSB weight data is stored in the MSB row section of the even field storage column section, and M-1 weight data is stored in the M-1 row of the even field storage column section. Area M-2 weight data is stored in the area M-2 of the even field storage column area. The M-6 weight data is stored in row M-6 of the even field storage column and the LSB weight data is stored in LSB row of the even field storage column.

As described above, a method of recording image data in the dynamic RAM for each weight will be described with reference to the memory map of FIG. 4.

8-bit image data is recorded in one column address. In the 640x480 mode, since 80 times (640 ÷ 8) of addressing is required per line, 80 rows are required for each row area. That is, the MSB line, M-1 line,... Each of the three sections, M-6 and LSB, consists of at least 80 rows. In addition, in the 853 × 480 mode, 107 (853 ÷ 8) addressings are required per line, in which case, the MSB line area, M-1 line area,... Each of the three sections, line M-6 and line LSB, consists of at least 107 lines.

Common to the above-described 640 × 480 mode and 853 × 480 mode, in the interlaced scanning mode, one frame is divided into odd and even fields, and both odd and even fields have 240 (480 ÷ 2) vertical lines. . Therefore, in order to record the data in the dynamic RAM by line, both the odd field storage heat zone and the even field storage heat zone both have 240 rows.

When odd field image data is input, the first to eighth sampled image data of the first line of the odd field is displayed in the first column of the first column in the first column {rows 1 MSB, first M-1, ...]. , 1M-6 rows, 1 LSB rows}, and the 9-16th sampled image data of the first line is stored as {second MSB row, 2M-1 rows,... , Lines 2M-6 and 2LSB} for each weight. If the above process is repeated 80 times (640 × 480 mode) to 107 times (853 × 480 mode), the image data of the first line of the odd field is displayed in the {MSB row area of the first column of the odd field storage column area. , Line M-1,… , Area M-6 and area LSB} are stored for each weight.

Next, the same procedure as described above is performed for the second to the 240th lines of the odd field, so that the image data of the second line of the odd field is stored in the {MSB row area, M− in the second column of the odd field storage column area. Area 1,… , Section M-6, section LSB}, by weight, Image data of line 240 of the odd field is stored in the column {MSB, M-1, ..., column 240 of the column area for storing the odd field; , Area M-6, area LSB} by weight.

Next, when even field image data is input, the first to eighth sampled image data of the first line of the even field is displayed in the first column {first MSB row, first M-1 row,... , 1M-6 rows, 1 LSB rows}, and the 9-16th sampled image data of the first line is stored as {second MSB row, 2M-1 rows,... , Lines 2M-6 and 2LSB} for each weight. In this case, if the above-mentioned 80 to 107 times are repeated, the image data of the first line of the even field may be displayed in the {MSB row area, M-1 row area,... , Area M-6 and area LSB} are stored for each weight.

Next, the above-described method is performed on the second to the 240th lines of the even field, so that the image data of the second line of the even field is stored in the second column of the even field storage column area {MSB row area, M-1. Row area,… , Section M-6, section LSB}, by weight, The image data of the 240th line of the even field is stored in the {MSB line, M-1 line,. , Area M-6, area LSB} by weight.

A method for reading image data recorded in the dynamic RAM for each subframe by the above-described method will be described with reference to the memory map of FIG. 4.

First, when a data read signal is input, the data stored in the MSB row area of the first column is sequentially read from the odd field storage column area to read all the MSB weight data of the first line, and then into the even field storage column area. By jumping, data stored in the MSB row region of the first column is sequentially read to read all the MSB weight data of the second line.

Next, jump to the odd-field storage column again to read all MSB weight data of the third line from the second-row MSB row, and then jump back to the even-field storage again and then to the second-row MSB row. Read MSB weight data of the fourth line from the zone.

As described above, while jumping alternately between the odd field storage thermal zone and the even field storage thermal zone, an odd number of lines (first line, third line) from the MSB row zone of the odd field storage thermal zone Reads the MSB weight data of the fifth line, the fifth line, the 477th line, and the 479th line, and the even line (second line, fourth line, By reading the MSB weight data of the sixth, ..., 478, 480th lines, all MSB subframes of one frame can be obtained.

In addition, the reading method as described above may include M-1 weight data, M-2 weight data,... , M-6 weight data, LSB weight data. That is, M-1 weight data of an odd line for one frame is read from the M-1 row area of the odd field storage thermal zone, and one frame from the M-1 row area of the even field storage thermal zone. When the operation of reading even-numbered M-1 weight data is alternately performed 240 times, an M-1 subframe of one frame can be obtained. Reading the odd line LSB weight data of one frame from the LSB row section of the odd field storage column section, and reading the LSB weight data of even frame of one frame from the LSB row section of the even field storage column section. When the operation is alternately performed 240 times, an LSB subframe for one frame can be obtained.

As described above, the present invention can provide a method of recording interlaced image data into a frame memory using a dynamic RAM having a relatively low cost, and providing a method of reading image data from the frame memory, thereby improving circuit reliability. In addition, the cost can be reduced.

Claims (2)

A method of sampling an interlaced composite video signal, classifying it by weight through a PISO unit, and then recording it in a frame memory using dynamic RAM, Dividing the dynamic RAM into an odd field storage heat zone and an even field storage heat zone; The dynamic RAM is divided into MSB weight storage row zone, M-1 weight storage row zone, M-2 weight storage row zone,. A second step of dividing the M-6 weight storage row region and the LSB weight storage row region; When odd field image data is input, the first to eighth sampled image data of the first line of the odd field is displayed in the first column of the first column in the first column {rows 1 MSB, first M-1, ...]. , 1M-6 rows, 1 LSB rows}, and the 9-16th sampled image data of the first line is stored as {second MSB row, 2M-1 rows,... , Rows 2M-6 and 2LSB}, respectively, and the image data of the first line of the odd field is stored in the {MSB row area, the first column of the odd field storage column area by repeating the above process. Area M-1,… A third step of storing the respective weights in the M-6 region and the LSB region; The third process is repeated for the second to the 240th lines of the odd field, so that the image data of the second line is stored in the {MSB area, M-1 area,. , Section M-6, section LSB}, by weight, The image data of the 240th line is the {MSB line, M-1 line,. A fourth step of storing the respective weights in the M-6 region and the LSB region; When even field image data is input, the first to eighth sampled image data of the first line of the even field is selected from the {first MSB row, first M-1 row,. , 1M-6 rows, 1 LSB rows}, and the 9-16th sampled image data of the first line is stored as {second MSB row, 2M-1 rows,... , Rows 2M-6 and 2LSB}, respectively, by weight, and repeating the above process to store the image data of the first line of the even field in the {MSB row area, the first column of the even field storage column area; Area M-1,… A fifth step of storing the respective weights in the M-6 region and the LSB region; The third process is repeated with respect to the second to the 240th lines of the even field, and the image data of the second line is stored in the {MSB area, M-1 area,. , Section M-6, section LSB}, by weight, The image data of the 240th line is the {MSB line, M-1 line,. And a sixth process of storing each weight in the M-6 area and the LSB area, respectively, in the dynamic RAM. In the column field for storing odd field, sampled image data of odd field is recorded by weight and each line, and in the field field for storing even field, sampled image data of even field is recorded from dynamic RAM recorded by weight and each line. In a method of reading image data of one frame for each subframe, A first step of sequentially reading the data stored in the MSB row region of the first column in the odd field storage column region to read all the MSB weight data of the first line; A second step of jumping to an even-field storage column region and sequentially reading data stored in the MSB row region of the first column to read all the MSB weight data of the second line; Jump to the odd field storage column section to read MSB weight data of the third line from the MSB row section of the second row, jump to the even field storage column section and jump to the MSB row section of the fourth line from the MSB row section of the second column. The weight data is read, and the above process is repeated to read the MSB weight data of an odd number of lines from the MSB row section of the odd field storage column section, and from the MSB row section of the even field storage column section. A third step of reading MSB weight data of even lines for one frame; And In the same manner as in the first to third processes, M-1 weight data of odd lines for one frame is read from the row M-1 of the odd field storage thermal zone, and M of the even field storage thermal zone is read. Read M-1 weight data of even lines for one frame from the -1 row area, and read all M-1 weight data for one frame; And read odd-line LSB weight data of one frame from the LSB row section of the odd-field storage column section, and read LSB-weight data of even lines of one frame from the LSB row section of the even-field storage column section. And a fourth process of reading out all the LSB weight data for one frame, from the dynamic RAM.