Hi, I am new to N79E059A 40 pin DIP package. This controller has 4k Data EEprom for storing or reading the data. I am able to write to data eeprom. Any guidance on writing the data flash will be helpful.
Flash is just a cooler name for describing that the EEPROM memory happens to support fast block-sized or full device-sized erase while the older and more traditional EEPROM requires individual cells or small blocks of maybe 8-32 bytes to be erased at a time.
same thing simpler flash (usually) refer to parallel addressable memory, EEPROM (usually) refer to serial memory
But the simplification isn't really simpler, since there is a significant difference in how EEPROM/flash is used that goes beyond if the memory has a serial or a parallel interface.
With a EEPROM, you normally directly write the data without any erase request. If the erase block size is larger than one byte, then the chip hides this internally. So the EEPROM behaves like a RAM but with different access times for reads and writes. And with the limitation that the cells wears out.
With flash, you need to erase the block before writing - unless for some types of flash if you just wanted to add more data to a block that had the last part already erased. So whatever interface the memory has, the program code will be nowhere near how you access RAM or EEPROM.
Serial/parallel is more a question of size. A flash fits more - normally much, much more - data per surface unit because the simplification of having block-erase. So flash memory chips are normally hundreds of kilobits up to many gigabits large. And it's meaningful to have a parallel interface if the memory is large, to give higher bandwidth.
Because of the very large cell size of a EEPROM, they very seldom get past a couple of megabit and are often down in the kilobit size range. So it's normal to optimize for pin count, unless the EEPROM happen to be internal to the processor where they tend to be direct-mapped, allowing trivial writes like:
eeprom[addr] = value;
But the main question in this thread is if the OP is talking about the program storage, so requesting help with IAP.