autofan1965
Member
Pcf7946 are mask rom with eeprom area to write data with lf interface only, pcf other then 7946/7947 are mask rom+flash+eeprom with interface wich must make possible to flash firmware. Trick wich is done by all is just complete erase+write correct fw back+default eeprom data. As 7946/7947 have no interface for programming how you will do it? Its similar case to 8E chip with unknown 12byte.