> but I'm not getting anything on the 'debug port'.

Did you put "set COM x" into your default.txt?  I'm not sure if 
STUART is 2 or 3 on your device (WinCE can re-order them!).


> I assume that I should alter it to use STUART instead, for my
> handheld, but do you know whether or not the uart stays
> initialized or functional until the moment haret jumps to the
> linux kernel?

Yes, it normally stays initialized.

But keep in mind that some device can turn on/off the power to 
serial line drivers, to conserve power. You'd need to turn that 
on. Here HaRET comes handy: you can reprogram those STUART pins 
as normal GPIO pins and then set binary values and look with a 
scope/voltmeter if you get something out. Similar you can test 
the RxD pin.

That leads me to the thought that for the STUART to work the 
GPIOs must properly programmed, look at the GAFR registers.

And finally some CPUs have clocks that they can turn off to 
conserve power. Look if the clock for STUART is running.

One thing that you can do is to run some WinCE-based terminal 
program and test the STUART with that. While it runs, you can 
use HaRET to examine the status of various registers.


> I would imagine, in any event, that the Linux 
> kernel has code to initialize the uarts as necessary (e.g. if
> console=ttyS2 <=> stuart).

Yes, normally this works.

Also note that Linux for ARM cpus has some early debug capability 
via the serial port (e.g. debug output during decompression, 
before the MMU get's turned on). See

http://lists.arm.linux.org.uk/lurker/message/20081210.174754.29691349.en.html
http://amitshah.bizhat.com/arm/arm_linux_boot-1.html
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