HN58V65AI/HN58V66AI/HN58V65A-SR/HN58V66A-SR Series

Rev.3.00, Feb.02.2004, page 21 of 26

act as a trigger and turn the EEPROM to program mode by mistake. To prevent this unintentional

programming, the EEPROM must be kept in an unprogrammable state while the CPU is in an unstable

state.

Note:

signal.

CPU

RESET

Unprogrammable

Unprogrammable

*

*

2.1 Protection by

CE, OE, WE

To realize the unprogrammable state, the input level of control pins must be held as shown in the

table below.

CE

×

×

OE

×

×

WE

×

×

×: Don’t care.