toaruos/kernel/core/serial.c
2011-12-10 17:34:10 -06:00

77 lines
1.5 KiB
C

/* vim: tabstop=4 shiftwidth=4 noexpandtab
*
* Serial Port Driver
*/
#include <system.h>
#define SERIAL_PORT_A 0x3F8
#define SERIAL_PORT_B 0x2F8
#define SERIAL_PORT_C 0x3E8
#define SERIAL_PORT_D 0x2E8
void
serial_handler(
struct regs *r
) {
char serial = serial_recv();
/*
* Fix the serial input assuming it is ascii
*/
switch (serial) {
case 127:
serial = 0x08;
break;
case 13:
serial = '\n';
break;
default:
break;
}
if (keyboard_buffer_handler) {
keyboard_buffer_handler(serial);
}
}
void
serial_install() {
/* We will initialize the first serial port */
outportb(SERIAL_PORT_A + 1, 0x00);
outportb(SERIAL_PORT_A + 3, 0x80); /* Enable divisor mode */
outportb(SERIAL_PORT_A + 0, 0x03); /* Div Low: 03 Set the port to 38400 bps */
outportb(SERIAL_PORT_A + 1, 0x00); /* Div High: 00 */
outportb(SERIAL_PORT_A + 3, 0x03);
outportb(SERIAL_PORT_A + 2, 0xC7);
outportb(SERIAL_PORT_A + 4, 0x0B);
irq_install_handler(4, serial_handler); /* Install the serial input handler */
outportb(SERIAL_PORT_A + 1, 0x01); /* Enable interrupts on receive */
}
int
serial_rcvd() {
return inportb(SERIAL_PORT_A + 5) & 1;
}
char
serial_recv() {
while (serial_rcvd() == 0);
return inportb(SERIAL_PORT_A);
}
int
serial_transmit_empty() {
return inportb(SERIAL_PORT_A + 5) & 0x20;
}
void
serial_send(char out) {
while (serial_transmit_empty() == 0);
outportb(SERIAL_PORT_A, out);
}
void
serial_string(char * out) {
for (uint32_t i = 0; i < strlen(out); ++i) {
serial_send(out[i]);
}
}