JPH0291727A - Read/write control system for control information - Google Patents

Abstract

PURPOSE:To easily read and write the control information and to save the space by varying and writing default values in a serial PROM(programmable ROM) through registers. CONSTITUTION:This system is equipped with the serial PROM 120 stored with the default values required to control a computer main body or peripheral device, an access register 105 which is used when a CPU 100 accesses this PROM 120, and a PROM interface circuit which reads the default values out of the PROM 120 and writes them in the register 104 after a reset signal is detected. Then the default values are varied and written in the PROM 120 through the registers 104 and 105. Consequently, the control information of a control board is easily read and written and a serial EEPROM(Electrically Erasable PROM) is used to save the space.

Description

DETAILED DESCRIPTION OF THE INVENTION [Objective of the Invention (Field of Industrial Application)] The present invention relates to a read/write control system for a 7"7 ortho1 of information necessary for controlling a combination.

(Prior art) The information necessary for controlling the combination, if the value does not change, is stored in EPROM (Eraaab) using a ROM writer.
le Programmable ROM) VC*
It is common to use it as an input. In addition, if it was necessary to change the default value, it was written in the RAM, and the control was then carried out by the control software.

(Problem to be solved by the invention) By the way, when writing data to KPROM, the ROM
A writer must be used, and it takes time and effort to write and change data, and there is no suitable capacity, resulting in large scale and high costs. When storing in RAM, 'pa, qua, f' by battery is required. Furthermore, if the control software is provided with the control software, there are various problems such as the need for an external storage device.

The invention was made in view of the above-mentioned shortcomings, and provides a control system for reading and writing information that reduces the need for reading and writing control information and saves space. The purpose is to

[Configuration of the Invention (Means for Solving the Problems)] The present invention comprises a serial PROM in which a 7"7 ortho drive necessary for controlling the main unit or peripheral devices is stored, and a CPU in this PROM. It is equipped with an access register used when accessing, and a PROM interface circuit that reads out the 7'#7 ortho value from the PROM after detecting the reset ID and inputs it into the register.
The configuration is such that the 7'h7 ortho value for the ROM is changed and stored via the register.

(Function) According to the above-mentioned configuration, the serial PROM Kr7 ortho value is written on the control board via the register for storing control information that can be input/output accessed from the CPU, and after the reset signal is checked, this control information is written from the serial PROM. It is equipped with a serial PROM interface circuit for reading and writing to the control information storage register. IJPROM (E
l*ctrioally Erasable PROM
), it saves space.6
Ru.

The CPU can read the control information without being aware of the serial EEPROM, and can change and write the control information using software.

(Example) Hereinafter, an example of the present invention will be described in detail using the drawings. FIG. 1 is a schematic diagram showing an embodiment of the present invention. In the figure, 100 is a CPU.

120 is a serial) JPROM. 102 is a data bus that connects the CPU through the controller
,! A real EEPROM 7xo is connected. 103 is a signal line through which a reset signal (RgiT) flows.

Reference numeral 104 is a register, consisting of a shift register with a capacity of several words, and is used to store serial data. Rarel r-
Convert to evening. 105 is also a register, data bus 1
The I/O silkworm issue that transfers 02 is the selector 116 that will be described later.
It is possible to connect to the EEPROM 120 via the .

106 is a black signal generation circuit (CLOCK),
The signal 112 activates the EEPRO.
Generates a synchronization signal (line 107) for M120. The signal transferred on line 107 is a synchronization signal, EE
Used to synchronize with PROM 120. 10
8 is a read/write control circuit (IVvi) p, E
It determines whether the operation of EPROM J 20 is read or write, and outputs it to line 109. Transfer line 109; 6 signal is READ/WRITE signal 6D, which is supplied to EEPROM 120K via selector 115.

A word counter (WDC) 110 has a built-in counter, and supplies data (life 122) t-count output from a data counter 113 (described later) to the selector 115 via a line 111. It also has the function of enabling the selector 115 via line 112 by inputting a reset signal (line 103) and disabling it when the counter reaches a predetermined value.

The signal transferred on line 111 is the select (CS) signal of EEPROM 120, which is provided to EEPROM J 20 via selector 115 (and line 118). The signal transferring line 112 is an interface circuit enable signal, and while this signal is enabled, data in JJPROM 120 is transferred to register 104.

A data counter (DTC) 113 has a built-in counter. It detects a dummy ``0'' output at the beginning of the data, starts counting, and outputs a signal to that effect via line 122 when one word data transfer is completed.

114 is a serial signal data line, and selector 115
is connected to data line 119 via n.

115 is a selector. Selector 115 selects line 1
When 12 is enabled, it selects the signal on the interface circuit side, and when it is in guimo pull mode, it selects the signal output from register 105 and supplies it to serial EEPROM J 20 via line 116. -line 116
The signal transferred is a signal clock (8K), which is a synchronization signal with the serial EEPROM IZO.

The signal that transfers line 117 is the READ/WRITE signal (RD//vrfL) te, -z riffle EEPRO
This is the signal that determines the M I J 0 O operation t.
8 becomes enabled when 120 is selected by the chip select signal (C8). 119 is serial data (
DATA) input/output line, serial EEPROM 12
Used for input/output of serial data from 0. 122
In the word clock, data for one word is stored in register 1.
It is output when the transfer to 04 is completed. 123 is register 1
05 corresponds to the Do ratio output, and 124 corresponds to the D of the register 105.
I output, 125, to D2 output of register 105, 126
corresponds to D3 manual power of register 105.

FIG. 2 is a timing chart showing the operation of the serial EEPROM J;20. In the figure, 201
is a synchronous clock, and data is input and output in synchronization with this clock. 202 indicates the input/output timing of serial data. 203 is READ/WR
If the state of the ITE signal JQ t is 40, HIGH, a read operation is performed, and if it is LOW, a write operation is performed. 204 indicates the state of the chip select signal, which in this case is chip enable.

Hereinafter, the operation of the actual ball example of the present invention will be explained in detail. ′
1. Serial EEPROM 120 to register 10
4 will be explained. Initially, when the reset signal (line 103) is output, the word counter 110 outputs the enable signal (line 112).

When the black/red signal generating circuit 106 detects the line 112, it outputs the black/red signal as shown in timing 201 in FIG. 2 via the line/10';rt-. When the selector 115 detects the line 112, it selects the B terminal input (consisting of Bl-84) and selects the serial EEPROM J
;l Connect to O. At this time, word counter 110 outputs a chip select signal via line 111.

Then, the read/:y write control circuit 108 controls the line 1
Set 09 to @HIGH” level and serial EEPR
Notify OM 120 of read operation violation. At this time, after counting one word, the data counter 113 instructs to output one word of data to the register 104 via the line 122. During the above period, the register 104 stores data in the register 104 according to timings 201 and 202 in FIG. The above operation is repeated until the value of the built-in counter of the word counter 110 reaches the specified number of 1s.

Next, from the CPU 100, serial F2EPROM I
Access to JO will be explained. register 105
0 input/output is serial EEPKM via selector 115f
Since it is directly connected to 120, for example, "0001", "0000",
"0001'".

If you write data as 'oooo', line 12
3 becomes a slope like 201 shown in FIG.

Here, serial EEPROM using selector 115
120 r-talid will be explained. Selector 11
If the enable signal (line 112) is not detected, the A terminal side made of Al-A4 is selected and connected to each signal line of the serial EEPROM J J O. Next, IC1 writes @1100” into register 105.
CS HIGH, RD/Wll HIGH, tells the serial EEPROM J 20 to start a read operation. This state is T1 shown in FIG. Then, in register 105, “1101
”, it will be in the T2 state.

When the above steps are completed, the state becomes T2'. At this time, if you read the register 105, you can read 'IIDATAI''tl-.At this time, the 2nd pin and the
The data is from M120. @11 in register 105
When 00'' is written, the state becomes T3. By repeating the above operation, the data in the serial gEPROM J20 can be read.

Next, from CPU 100 serial EEPROM J 2
How to write data to 0 8!1. fJA. First, if the selector 115 does not detect the enable signal 112, it selects the A terminal side and outputs the serial EEP.
Connect to the signal line of ROM J 2o. Next, by writing data @1000'' to the register 105, the data is set to 204 HIGH 1Z 03 '' as shown in FIG.
'LOW' tells the serial jJPROM 120 to start a write operation. This state is TI.

When the above is completed, the state becomes TI'. At this time, @l0DATAIOn is written to the register 105. Then, write @10DATA 11″ to the register ios.

Then, 201 in Figure 2 starts up and the serial EEPR
OM 120 takes in the value on 202 at this time as data. This state is T2. Then register x
When osK "10DATAI O" is written, the state becomes T3.

If you repeat the above operation, serial EEPROMJJO
data can be written to.

[Effect of the invention According to the invention as explained above, C10 is serial E
EPROM t- Control information can be read out unconsciously, and control information can be changed and set using software. In addition, since a serial EEPROM is used, there is no need for batteries, and the device is small and inexpensive. The present invention can be used to store the default value of the mode of a printer, etc., the default 1st shift of a disk gray, the storage of the physical address of a LAN mate, etc.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an embodiment of the present invention, and FIG. 2 is a timing chart showing the operation of a non-inventive embodiment. 104...Register, 105...Register, 106
...Clock, signal generation circuit (CLOCK), J o
g...y-do/, phyto control circuit (R/W), J
J o... Ward Callan p (wDc), 11 J
-f"-fi Counter (DTC), 115...Selector, 120...Serial EEPROM.

Claims (1)

[Claims] A serial PROM (programmable ROM) that stores default values necessary for controlling the computer main body or peripheral devices, an access register used when the CPU accesses this PROM, and a default value read from the PROM after a reset signal is detected. A read/write control method for control information, comprising: a PROM interface circuit for writing into the register, and changing and writing a default value to the PROM via the register.