CXP921064A Datasheet, PDF (30/33 Pages) Sony Corporation – CMOS 16-bit Single Chip Microcomputer

CXP921064A
Notes on PF7 Usage
FLASH EEPROM incorporated PF7 is also used as flash mode setting function. Note the followings:
1. "H" is output to PF7 during a reset. That is driven at comparatively high impedance (approximately 150 kΩ),
and take care that VOH should not fall under 0.7 VDD by the partial pressure with external circuit load
impedance.
2. When using software reset functions, PF7 may not rise enough during a reset. Switching PF7 to "H" output
prior to software reset execution or connecting pull-up resistor is recommended.
RST
PF7
Keep PF7 above 0.7 VDD during
this period.
Normal operation
Flash mode
Mask ROM and piggy/evaluation chip do not have flash mode setting function. Considering that EEPROM
incorporated type is used, above countermeasure should be performed.
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