ARM7 UART0

Development Boards MicroMod
1

OK I’m having difficulty with UART0 on my LPC2468. Here’s my trouble. A couple months back I wrote a small program just to see how the UART works. Got it up and running. Now I went to reload it and no dice.

I monkeyed with the board for quite a while. All the sudden it started running again. No idea what I did, it was the same code as before. Took a break. Came back to add more to the code. UART stopped working so I reverted back to my code that I had working before. No dice, stopped working.

I thought maybe I had a hardware issue so I tried 3 separate PC’s, 2 different cables, and two different development boards. Same store on all of them. When I plugged in the other development board the code immediately worked. However, upon reloading new code / power cycling the UART stopped working a refused to go again.

Any ideas?

Here’s my code. I’m using the standard Kiel uVision3 bootup:

#include "lpc246x.h"

int main( void )
{
	char TX = 't';
	
	PINSEL0		= 0x00050050;	// Hookup UART0 - Page 170
	PCONP		= 0x00000018;	// Power on UART0 - Page 60
	PCLKSEL0	= 0x00000000;	// Peripheral clock - Page 55
	
	// Setup UART0 - Page 438
	U0LCR		= 0x00000083;	// 8 bits, no parity, 1 stop bit
	U0DLL		= 0x000000C2;	// 9600 bps @ 30MHz VPG Clock
	U0LCR		= 0x00000003;	// DLAB = 0
	
	while( 1 )
	{
		while( !(U0LSR & 0X20 ) );
		U0THR = TX;
	}

	return 0;
}