util/romcc/tests/simple_test15.c

   1 static void outb(unsigned char value, unsigned short port)
   2 {
   3         __builtin_outb(value, port);
   4 }
   5
   6 static unsigned char inb(unsigned short port)
   7 {
   8         return __builtin_inb(port);
   9 }
  10 static int uart_can_tx_byte(void)
  11 {
  12         return inb(0x3f8 + 0x05) & 0x20;
  13 }
  14
  15 static void uart_wait_to_tx_byte(void)
  16 {
  17         while(!uart_can_tx_byte())
  18                 ;
  19 }
  20
  21 static void uart_wait_until_sent(void)
  22 {
  23         while(!(inb(0x3f8 + 0x05) & 0x40))
  24                 ;
  25 }
  26
  27 static void uart_tx_byte(unsigned char data)
  28 {
  29         uart_wait_to_tx_byte();
  30         outb(data, 0x3f8 + 0x00);
  31
  32         uart_wait_until_sent();
  33 }
  34
  35 static void print_debug(const char *str)
  36 {
  37         unsigned char ch;
  38         while((ch = *str++) != '\0') {
  39                 uart_tx_byte(ch);
  40         }
  41 }
  42
  43 static void main(void)
  44 {
  45         print_debug("one\r\n");
  46         print_debug("two\r\n");
  47 }