Lpc2000

A more general, simpler alternative is as follows:

/* Transmit specified string to DEBUG port, using polled i/o */

void polled_write_to_uart_0(char *s)

{
  unsigned int status;

  while (*s)
  {
    do
    {
      status = REG(UART0_LSR);
    } while (!(status & 0x20));

    REG(UART0_THR) = (uint) *s;

    s++;
  }

  return;
}

/* example call: */

  polled_write_to_uart_0("Hello world\n");

This assumes the UART has been initialsed correctly and interrupts 
disabled.

It's a handy "first test" to do to see if the UART setup is correct.

Brendan

--- In lpc2000@yahoogroups.com, "fordp2002" <SimonEllwood@...> wrote:
>
> --- In lpc2000@yahoogroups.com, "ian.scanlon" <scanlon.design@> 
wrote:
> > 
> > Does writing directly to the uart tx register work? How about 
putc ?
> >
> 
> writing directly works very well as long as you do not overfill the
> fifo's.
> 
> here is some code I wrote earlier ;)
> 
> typedef union
> {
> 	unsigned long whole;
> 	unsigned char part_byte[4];
> } four_bytes;
> 
> void UNDEF_Routine(void)
> {
> 	register unsigned int *lr_ptr asm("r14");
> 	
> 	four_bytes temp;
> 	temp.whole = (usigned long) lr_ptr;
> 	UART0_THR = 	temp.part_byte[3];
> 	UART0_THR = 	temp.part_byte[2];
> 	UART0_THR = 	temp.part_byte[1];
> 	UART0_THR = 	temp.part_byte[0];
> }
> 
> By the way thanks to the guys who helped me with reading the Link
> Regitser.
>