Convert ATmega 32A [µC] to EEProm Hi There, I am Prince Kumar,
So I am getting to the point:- I am Using ATmega 32A Microcontroller and Convert it into an EEProm, You can use that EEProm anywhere its whole Design is very same to some most popular, handsome and good looking ICs EEProms like:- ATmega, SST, WesternCenter etc. Microcontroller is Programmed according to the Working of an real EEProm same as AT28c256 but its has a 16-bit(1-word) Address Bus Line and 8-bit Data Bus , with a 4-bit Control Bus.
Control_Bus
PINC0 -> CE Chip Enable
PINC1 -> OE Output Enable
PINC2 -> WE Write Enable
PINC3 -> ED Erase Data
Address_Bus
PINA0 - PINA7 Address Bus [Outer Bits]
PINB0 - PINB7 Address Bus [Inner Bits]
*Note: This is the order of Address_Bus and data is start filling from outer-bits to inner-bits you can say: 0x0000(0) is a 16-bit Number represents 0 and 0x0001(1) [0000 0000 0000 0001]. Hence, if you put A0 high and rest of pins low means Address ([1] Decimal) is selected.
Data_Bus
PIND0 - PIND7 Data Bus (8-bit Data)1-byte
[D7, D6, D5, D4, D3, D2, D1, D0]*
Hence, Address Bus -> PORTB , PORTA [16-bit Bus] Data Bus -> PORTD [8-bit Bus] Control Bus -> PORTC [8-bit Bus], But we are using only 4-bits to Control Memory.