Intel 8255
The Intel 8255 (also i8255 ) is a programmable parallel input / output component that was primarily developed for the Intel 8085 processor. It was later used with the Intel 8086 and its successors. The module is supplied in a 40-pin DIL housing . He was u. a. licensed to AMD , Mitsubishi Electric , National Semiconductor , NEC and Siemens .
The Intel 8255 is best known for its use in the parallel port of IBM PCs. But it was also used in PCs such as the SV-328 and the MSX computers.
The Intel 8255 has three 8-bit wide IO ports that are combined into two port groups (port group A and port group B).
- Port A (PA0 to PA7) and PC4 to PC7 of port C form port group A.
- Port B (PB0 to PB7) and PC0 to PC3 of port C form port group B.
The port groups can be operated in different modes. There is a control register for this which can be written via the data bus (D0-D7).
Intel D8255
Intel C8255-8
Literature and data sheets
- Horst Pelka: Practice with microprocessors , 2nd edition, Franzis-Verlag, Munich 1980, ISBN 3-7723-6582-5 , pp. 54-58.
- Microcomputer modules, data book 1979/80, volume 3, peripherals, Siemens AG, order number B 2049, pp. 124-164.
- NEC Electronics (Europe) GmbH, 1982 Catalog, pp. 657-664.