8255 is a programmable peripheral interface.
It contains three i/o port that can be programmed in different mode.
It is a general purpose programmable parallel i/o device.
It contains s a control register that can be programmed to control the function of port as well as it can also control that which mode they should operate.
It is a programmable parallel i/o device.
It consists of three input/output ports each of 8 bits. It has been arranged as two 8 bit ports and two 4 bit ports.
It has been arranged in two groups each of 12 bits.
It is TTL compatible also.
It also provides facility for the direct set and reset for port C.
It can operate in three modes:
1 Mode 0
2 Mode 1
3 Mode 2