Lpc2000

Version 2 of the UART, Blinky LED codeis now posted.  I went ahead and
protected the code which re-enables the uart interrupt in addition to
when it is disabled.  While the demo code does not have a preemptive
OS, if it did, it would be possible (not probable) for another process
to sneak in during the execution of the RMW sequence and modify the
mask.  The protection closes that possibility.

As a side note.  The disabling and restoring of the global interrupt
flag in the cpsr can has a similar problem.  It has to do with the
processor actually having multiple psr's and preemptive processes
doing the same thing to it while the main line code thinks it is
either enabling or disabling the current IRQ bit.  However, without
preemptive processes or ISR's which muck with the interrupt flag bits,
I don't believe there is a problem.  For more info on this, Atmel has
an APP note discribing it on their web site in the AT91 ARM7 section.

Regards
-Bill Knight
R O SoftWare