51單片機(jī)串行口速率設(shè)置

/*

51單片機(jī)速率設(shè)置公式

波特率=SYSclk/(32*12*(256-TH1)

*/

#ifndef MONITOR51SCON  = 0x50;		/* SCON: mode 1, 8-bit UART, enable rcvr      */TMOD |= 0x20;               /* TMOD: timer 1, mode 2, 8-bit reload        */TH1   = 221;                /* TH1:  reload value for 1200 baud @ 16MHz   */TR1   = 1;                  /* TR1:  timer 1 run                          */TI    = 1;                  /* TI:   set TI to send first char of UART    */#endif