8155是作为输入输出以及RAM扩充的IC.特性如下： 256字节的RAM。一组可编程6位IO口。两组可编程8位IO口。可编程14位二进制计时计数器。 多工地址和数据总线。内部地址锁存。8155采用40脚双列直插封装，单一＋5v电源。-8155 as input and output, and RAM expansion of IC. Features: 256 bytes of RAM. A programmable six IO port. Two programmable 8-bit IO port. 14-bit binary counter programmable timer. Multiplexing address and data bus. Internal address latch. 8155 in a 40-foot two-line package, single+5 v power.