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#define FOOLOS_MODULE_NAME "serial"
#include "serial.h"
#define PORT 0x3f8 /* COM1 */
void serial_init() {
x86_outb(PORT + 1, 0x00); // Disable all interrupts
x86_outb(PORT + 3, 0x80); // Enable DLAB (set baud rate divisor)
x86_outb(PORT + 0, 0x03); // Set divisor to 3 (lo byte) 38400 baud
x86_outb(PORT + 1, 0x00); // (hi byte)
x86_outb(PORT + 3, 0x03); // 8 bits, no parity, one stop bit
x86_outb(PORT + 2, 0xC7); // Enable FIFO, clear them, with 14-byte threshold
x86_outb(PORT + 4, 0x0B); // IRQs enabled, RTS/DSR set
// log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"COM 1 - initialized");
}
int serial_received() {
return x86_inb(PORT + 5) & 1;
}
char serial_read() {
while (serial_received() == 0);
return x86_inb(PORT);
}
int is_transmit_empty() {
return x86_inb(PORT + 5) & 0x20;
}
void serial_write(char a) {
while (is_transmit_empty() == 0);
x86_outb(PORT,a);
}
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