Lpc2000

It was a small oversite that it wasn't posted.  I was copying stuff
out that I didn't need.  Since then I've made another small project
that just tests the UART.  I am now trying non vector irqs, and they
still don't work.  Here is the correct code:


#include <stdio.h>
#include "../ArmCommon/types.h"
#include "../ArmCommon/LPC22xx.h"
#include "../ArmCommon/LPC2294.h"

#define TX_BUFFER_LENGTH 64

static Uint16 txBytes = 0;
static Uint16 txRdPos = 0;
static Uint16 txWrPos = 0;
static Uint16 txBuffer[TX_BUFFER_LENGTH];

void uart0_config (void);
void uart0_isr (void);
void uart0_sendByte (Uint8);
int putchar(int);
int main (void);

void uart0_config (void) {
	// Setup UART 0
	U0LCR = 0x80; // Enable DLAB
	U0DLL = 0x36; // Setup BGR
	U0DLM = 0x00; // ~57.6 kbps @ 50 Mhz
	U0LCR = 0x03; // Enable UART 0, 8 bits, no parity, 1 stop bit

	// Reset the FIFOs
	U0FCR = 0xC7; // RX FIFO trigger level 8 chars, reset tx and rx fifo,
enable fifos

	// Setup Interrupts for UART0
	VICIntSelect &= 0xFFFFBFFF;	 // Make sure 6 is IRQ not FIQ
	VICIntEnable |= (0x1 << 6); // Enable Uart0 Interrupt
	VICDefVectAddr = (unsigned long) uart0_isr; // Use Non vectored irq
	U0IER = 0x7;		
}

void uart0_isr (void) __irq {
	Uint8 dummy;
	switch(U0LSR) {
		case 0x01: // RDR
			break;
		case 0x02: // OE
			break;
		case 0x04: // PE
			break;
		case 0x08: // FE
			break;
		case 0x10: // BI
			break;
		case 0x20: // THRE	
			if(txBytes != 0) {
				U0THR = txBuffer[txRdPos];
				txRdPos++;
				txRdPos = (txRdPos == TX_BUFFER_LENGTH)?0:txRdPos;
				txBytes--;
			}			
			break;
		case 0x40: // TEMT
			break;
		case 0x80: // FXFE
			break;
		default: // Must be CTI
			uart0_sendByte(U0RBR);	// Echo back
	}
	dummy = U0IIR; // read to clear IRQ
	dummy += 1; // keep compiler from optimizing dummy out
	VICVectAddr = 0;
}

void uart0_sendByte(Uint8 a) {
	// Wait until there is room in the buffer
	while(txBytes == TX_BUFFER_LENGTH);
	if(!(U0LSR&0x20)) { // Put it in the software buffer
		txBuffer[txWrPos] = a;
		txWrPos++;
		txWrPos = (txWrPos == TX_BUFFER_LENGTH)?0:txWrPos;
		txBytes++;
	}
	else { // If the chip buffer is empty, put it there
		U0THR = a;
	}
}

int putchar(int a) {
	uart0_sendByte((int)a);
	return 0;
}

int main (void) {
	PINSEL0 = PINSEL0_00_TxD | PINSEL0_01_RxD;
	VPBDIV = 0x1;
	uart0_config();
	printf("piece of crap!");
	while(1);
}

The output of this is "pep" when I run it on hardware.  The Keil
simulator of course says it is fine.

--- In lpc2000@yahoogroups.com, Robert Adsett <subscriptions@a...> wrote:
> At 02:33 PM 10/8/04 +0000, you wrote:
> >I do now have the VicVectAddr = 0;, but that doesn't help if it
> >doesn't get called.
> 
> Speaking of which, I just reviewed your code.  You don't appear to be 
> actually calling your uart initialization code anywhere (I don't see
how 
> you would get your baud rate right if you hadn't but...).  Also you
should 
> probably disable interrupts before disabling a specific interrupt via 
> VICIntEnClr
> 
> Robert
> 
> " 'Freedom' has no meaning of itself.  There are always restrictions,
> be they legal, genetic, or physical.  If you don't believe me, try to
> chew a radio signal. "
> 
>                          Kelvin Throop, III