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#ifdef DEBUG_SERIAL
#include "serial_com.h"
#include "port.h"
#include "jove.h"
static int
serial_com_recv(uint16_t port)
{
return inb(SERIAL_COM_LSR(port)) & 1;
}
static char
serial_com_getc(uint16_t port)
{
while(serial_com_recv(port) == 0);
return inb(port);
}
static int
serial_com_put_ready(uint16_t port)
{
return inb(SERIAL_COM_LSR(port)) & 0x20;
}
static void
serial_com_putc(uint16_t port, char c)
{
while(serial_com_put_ready(port) == 0);
outb(port, c);
}
int
serial_com_init_port(
uint16_t port,
uint16_t baud_divisor)
{
uint8_t div_low = (uint8_t)baud_divisor;
uint8_t div_high = (uint8_t)(baud_divisor >> 8);
outb(SERIAL_COM_IER(port), 0x00); // Disable all interrupts
outb(SERIAL_COM_LCR(port), 0x80); // Enable DLAB mode.
outb(SERIAL_COM_DLAB_BAUD_LO(port), div_low);
outb(SERIAL_COM_DLAB_BAUD_HI(port), div_high);
outb(SERIAL_COM_LCR(port), 0x03); // 8 bits, no parity, one stop bit.
outb(SERIAL_COM_FIFO(port), 0xC7); // Enable FIFO, clear them, 14 byte threshold.
outb(SERIAL_COM_MCR(port), 0x0B); // Enable IRQs, set RTS/DSR.
//Test to check if the serial port actually works.
outb(SERIAL_COM_MCR(port), 0x1E); // Set loopback mode.
outb(port, 0xAE); // Send test byte.
if(inb(port) != 0xAE) {
return 1;
}
//Set the port to normal operation mode.
//(no loopback, IRQs enabled, OUT#1 and OUT#2 enabled.)
outb(SERIAL_COM_MCR(port), 0x0F);
return 0;
}
void
serial_com_init(void)
{
if(serial_com_init_port(SERIAL_COM1, 3)) {
return;
}
}
int
serial_com_write(uint16_t port, const char *s, size_t len)
{
for(size_t i = 0; i < len; i++) {
serial_com_putc(port, s[i]);
}
return len;
}
#endif
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