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NEe Microcomputers, Inc.
NE'C
fLPD8255 fLPD8255A·5
PROGRAMMABLE PERIPHERAL INTERFACES
D ESCR I PTI ON
The IlPD8255 and IlPD8255A-5 are general purpose programmable INPUT/OUTPUT devices designed for use with the 8080A/8085A microprocessors. Twenty-four (24) I/O lines may be programmed in two groups of twelve (group I and group II) and used in three modes of operation. In the Basic mode, (MODE 0), each group of twelve I/O pins may be programmed in sets of 4 to be iniJut or output. In the Strobed mode, (MODE 1), each group may be programmed to have 8 lines of input or output. Three of the remaining four pins in each group are used for handshaking strobes and interrupt control signals.