Hello

What kind of changes should be done in pure 8051 12 Mhz firmware to port it to Atmel ATS89S8252?
Problem - project has 4k 8051 with external 2k ROM.
To decrease overall size of board an idea was
to use at89s8252 as it has internal eeprom which can be
use instead of external ROM.Direct transfer 4k 8051
firmware to AT89s8252 and 2k ROM to AT89S8252 eeprom
don't work.AT89S8252 should react to MOVX instruction
to read external eprom read and switch it to internal EEprom instead .Seems to be
it dosn't happend.Also the project is real-time
serial communication converter device so maybe it is
difference in clock/cycle command fetch between in pure 8051 and AT89S8252 ( assuming the same 12 mhz clock?