Casio PCR250 User Manual

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[Data reading procedure]
When the CPU read the dara of EEPROM, CPU send the CS signal and SK signal to EEPROM.
Then, CPU send the address to EEPROM, and then EEPROM send the data to CPU.
[Data writing procedure]
When the CPU save the data to EEPROM, CPU sends the CS and SK signal to EEPROM.
And CPU send the address and data to EEPROM from pin No.15.
When the EEPROM writes the data , EEPROM outputs the busy signal from DO terminal to CPU.
After finish writing, EEPROM outputs the ready signal from DO terminal to CPU.
CS
SK
DI
DO
Address
Data
Output data here
CS
SK
DI
DO
Address Data
High Impedance
BUSY(L)
READY(H)
Status

Casio PCR250 Specifications

General

Brand	Casio
Model	PCR250
Category	Cash Register
Language	English