8.1 可编程并行接口芯片8255A 8.2 可编程定时器/计数器芯片8253/8254 8.3 串行通信及可编程串行接口芯片8251A 8.4 模/数（A/D）与数模（D/A）转换技术 及其接口 -8.1 programmable parallel interface chip 8255A8.2 programmable timer/counter chip 8253/82548.3 serial communications and programmable seri

用VHDL实现Intel 8251的UART功能-Intel 8251 with VHDL realization of the UART Function

vhdl 实现的8251全部功能，非常实用-vhdl implementation of 8251 all of the features, very useful