Lpc2000

Hello all,

After trying to figur out what the heck is going on for over a day, I 
decided to throw the question in this group.

Just sending out a string through the UART1 of a LPC2294 is not 
working. Hope someone can give me the obvious solution to our 
problems.

The following components are used :
- Phytec demoboard with philips LPC2294
- Debug with amontec chamelion (Mcgraigor clone) on parallel port
- devlopment on IAR IDE for ARM

Software does the following :

- Initialising VIC :
   + Set default vector to dummy routine that does nothing, but 
returning
   + Set VICVectAddr 5 to int service routine for UART1
   + Set VICVectCtrl 5 to 0x27 (2 to enable int and 7 for UART1)
   + set UART 1 to IRQ (not FIQ in VIC Int Select register)
   + Enable the seventh bit of VICIntEnable (results in value 
0x00000080)
   + No other interrupts are enabled

- Initialise UART1 :
   + Set baudrate
   + set word length
   + set parity
   + set stop bit
   + flush fifo s by setting RFR and TFR bits in U1FCR and enable FIFO
   + set queue length
   + set pins of UART1 to TX and RX

- Send a string :
   + Copy string to output buffer (Somewhere in RAM)
   + Disable all interrupts
   + IF  transmit interrupt is not enabled (in UART1 register U1IER)
        THEN  Enable transmit interrupt (transmision was not busy)
              send first byte to UART1
        ELSE  Do nothing, transmission is busy, int will handle the 
rest
   + Enable interrupts again.

What happens, the first byte is send correct and received with 
terminal program. Next I see in the VIC registers the interrupt for 
the UART1 is pending, but the service routine is never called.
I even saw the int vector apearing in the VICVectAddr register, but 
the int is never serviced! Is there a global interrupt enable bit 
that I'm missing???

I had a breakpoint in the IRQ handling routine, but this was never 
called. Most is copied from a working demo. The only difference is 
that I do not wait for the byte to be transmitted. This is done in 
int.

the VIC init routine is the following :
========================================

tpVoid LPC210xInitVIC()
{
  // Setup interrupt controller.
  VICProtection = 0;
  // Disable all interrupts but the one used for the ROM monitor
  OSDisableInterrupts();
  VICDefVectAddr = (unsigned int)&DefaultInterrupt;
  VICVectAddr = 0x00;
}

//Dummy interrupt handler, called as default in irqHandler() if no 
other
//vectored interrupt is called.
tpVoid DefaultInterrupt()
{}

the int service routine is the following :
==========================================

// IRQ exception handler. Calls the interrupt handlers.
__irq __arm void irq_handler(void)
{
  void (*interrupt_function)();
  unsigned int vector;

  vector = VICVectAddr;   // Get interrupt vector.
  interrupt_function = (void(*)())vector;
  (*interrupt_function)();  // Call vectored interrupt function.

  VICVectAddr = 0;        // Clear interrupt in VIC.
}


The vector in the vector space of the IRQ (on address 0x18) is 
actualy a call of this routine. Checked with memory dump via J-tag.


Is there something we are missing.

Sorry to say but the documentation from Philips is not so clear on 
the use of the VIC nor the UART.

Thanks for your time,

Didier