pete286/serial.c

33 lines
703 B
C
Executable file

#include <dos.h>
#include "serial.h"
int comport = 0;
#define SER_LATCH_LO 0
#define SER_LATCH_HI 1
#define SER_TX 0
#define SER_LCR 3
#define SER_LSR 5
void ser_init(int port, int baudrate, int protocol) {
int far *comport_addr = MK_FP(0x0040, 0x0000);
int lcr;
comport = comport_addr[port];
outp(comport + SER_LCR, 0x80);
outp(comport + SER_LATCH_HI, baudrate >> 8);
outp(comport + SER_LATCH_LO, baudrate & 0xff);
outp(comport + SER_LCR, protocol);
}
void ser_write_byte(char byte) {
while (!(inp(comport + SER_LSR) & 0x20)) {}
outp(comport + SER_TX, byte);
}
void ser_write(char *str) {
for (; *str; str ++) {
ser_write_byte(*str);
}
}