Specifications

REV.-A
2.2.7 EEPROM Circuit
The EEPROM stores in its memory the current feed position of continuously fed paper, as well as the
current panel settings. This memory
is retained even after power is shut off.
EEPROM can memorize the current position of continuously fed paper, so that this information can be
maintained even if power goes off.
Figure 2-50 shows the
EEPROM circuit. Note that this is external to the CPU’s memory space.
EEPROM is selected when CPU port PC5 goes HIGH. Once EEPROM has been selected, the data to be
sent is set in CPU
port PB 1, and is fed bit-by-bit to the EEPROM in line with rising pulses from CPU port
PC4’S clock. Data are read, bit-by-bit, in line with falling clock pulses.
The
EEPROM receives commands to indicate whether to read or write data, and to indicate addresses.
CPU
ER59256
g PD78 10HG
( 1 c)
(2C)
DI
3
10
PB 1
DO
4
9
PBO
Cs ‘
22
1
PC5
7- TEST
CLK
2
21
PC4
RI 19
R120
33K 33K
777
Figure 2-50. EEPROM Circuit
2-45