Single-Chip Microcontrollers User's Manual

CHAPTER 5 EEPROM
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User’s Manual U10676EJ3V0UM
5.3 EEPROM Write Control Register (EWC)
The EEPROM write control register (EWC) is an 8-bit register used to control manipulation of EEPROM. Figure
5-1 shows its configuration.
Figure 5-1. Format of EEPROM Write Control Register
ERE
7
EWTC6
6
EWTC5
5
EWTC4
4
EWE
3
EWST
2
1
0
FCEH
Address
EWC
Symbol
EEPROM read enable flag
ERE EEPROM
0 EEPROM read disabled (suppresses current)
1 EEPROM read enabled (after 15
µ
s)
Dedicated EEPROM write timer clock selection bit
EWTC6 EWTC5 EWTC4 Selection of count clock
00018 × 2
13
/fX
00118 × 2
12
/fX
01018 × 2
11
/fX
01118 × 2
10
/fX
10018 × 2
9
/fX
10118 × 2
8
/fX
Other than above Setting prohibited
fX = system clock oscillation frequency
EEPROM write enable/disable control bit
EWE EEPROM write operation
0 Disable
1 Enable
EEPROM write status flag
EWST Write status
0 EEPROM write enable
1 EEPROM being written (EEPROM writing is not possible. If writing
is attempted, it is ignored.)