BarinkOS/kernel/drivers/serial/serial.cpp
Nigel 9c5667c454 Created a proper driver for the serial bus
* The driver can write to any of the pre-defined serial COM ports
* The driver can read from any of the pre-defined serial COM ports (Untested)
2023-10-28 21:51:04 +02:00

53 lines
1.1 KiB
C++

#include "serial.h"
#include "../../io/io.h"
// Initializes communication according to the spec given
Serial::Serial(SerialConfig config) {
port = config.port;
// Disable interrupts
outb(config.port + 1, 0x00);
// Enable DLAB
outb(config.port + 3, 0x80);
// set the baudrate
outb(config.port + 0, 0x03);
outb(config.port + 1, 0x00);
// configure for 8bits, no parity, one stop bit
outb(config.port + 3, 0x03);
// Enable FIFO, clear them, with 14-byte threshhold
outb(config.port + 2, 0xC7);
// Enable IRQ's, RTS/DSR set
outb(config.port + 4, 0x0B );
// Set in loopback mode, test the serial chip.
outb(config.port + 4, 0x1E);
// TEST
outb(config.port + 0 , 0xAE);
if(inb(config.port + 0) != 0xAE)
return ; // FAIL
outb(config.port + 4, 0x0F);
return ;
}
void Serial::write(void* data, int len) {
while (is_transmit_empty() == 0); // Wait for transmit queue to be free
for (int i = 0; i < len ; i++){
outb(port, ((uint8_t*)data)[i]);
}
}
char Serial::read() {
return inb(port);
}
int Serial::is_transmit_empty() {
return inb(port + 5) & 0x20;
}