Lpc2000

Thanks, I figured as much.  I found a couple of examples to download 
from ARM and they did it like this:

/* Setup the IRQ stack	*/
  mov  r0,#IRQ_MODE | I_Bit | F_Bit   /* IRQ_MODE, No Ints */
  msr  cpsr_c,r0                      /* Change the mode   */
  ldr  r13,=IRQ_STACK 	              /* End of IRQ_STACK  */

I assume that "r13" is the same as "sp" ?

They also have some RAM init code after stack setups.  I guess they 
are zeroing memory.  Do I need to zero RAM?  Does it really matter to 
anything?

Regarding IAR, I started out with that system and also MakeApp.  
After running into several bugs I am giving up and trying the GNU 
world.  It would spit out bad ELF files at times that my JTAG 
debugger could not load.  I ran into another bug where the compiler 
went into the weeds on a simple loop and then dropped every function 
call thereafter.  Bugs in MakeApp too.

They have a few nice extensions, such as the record structure into 
the bits of the regs. But all the bells, whistles, and optimizations 
in the world matter little when it keeps throwing bugs.  I could not 
trust it anymore.

Chris.