Lpc2000

Can someone point out a short quick example on how to get software
interrupts to work.  I'm using the Keil's toolset, but I can probably
figure it out if it works w/ GNU.

Basically what I am trying to do is get back into supervisor mode so I
can enable/disable IRQs and FIQs.  I have the enable/disable code
already, but it doesn't do anything since I'm not in supervisor mode.