并/串转换器即并行输入、串行输出转换器，例如一个8bit输入的并/串转换器，输出时钟频率是输入时钟频率的8倍，输入端一个时钟到来，8个输入端口同时输入数据；输出端以8倍的速度将并行输入的8bit串行输出，至于从高位输出还是从低位输出，可以再程序中指定。-And/or parallel series converter input, serial output converter, for example, a 8bit input and/series converter, the output clock frequency is the input clock frequency of 8 times, the arrival of a clock input, 8 input data input port at the same time　 output to 8 times the speed of 8bit parallel input serial output, as output from a high level or low output, the procedure can be specified.