Lpc2000

I'm developing with the LPC2220 processor, using IAR's Embedded
Workbench (4.30A and J-Link.  For some reason, about 30% of the time,
when I run code in debug mode (using C-Spy) my timer and/or processor
clock runs at incorrect speeds.  Yet when I end the debug session, low
assert the reset pin on the processor, and let it boot up using the
code in flash, all clock speeds will run at the correct speeds.  Is
there a register in the processor or a setting in the IAR Embedded
Workbench that I'm missing that would fix this problem?

If you single-step through the setup routine for the PLL, it is possible that this
kills the PLL  feed sequence and you'll probably be running at the crystal frequency.

I haven't tried this, but it's what I would expect. (The manual says the feed
sequence must occur in consecutive VPB bus cycles.)

Regards,
Danish

I do have PLL code (which does work when enabled), but I've been
running most all of the debugging with the PLL disabled (removing
calls to config PLL with "#ifdef USE_PLL") because of this problem. 
So this problem actually crops up while running with straight crystal
speeds (12.288MHz).

--- In lpc2000@yahoogroups.com, "Danish Ali" <danish@...> wrote:
>
> If you single-step through the setup routine for the PLL, it is
possible that this
> kills the PLL  feed sequence and you'll probably be running at the
crystal frequency.
> 
> I haven't tried this, but it's what I would expect. (The manual says
the feed

> sequence must occur in consecutive VPB bus cycles.)
> 
> Regards,
> Danish
>

Hi Jeff,

> I'm developing with the LPC2220 processor, using IAR's Embedded
> Workbench (4.30A and J-Link.  For some reason, about 30% of the time,
> when I run code in debug mode (using C-Spy) my timer and/or processor
> clock runs at incorrect speeds.  Yet when I end the debug session, low
> assert the reset pin on the processor, and let it boot up using the
> code in flash, all clock speeds will run at the correct speeds.  Is
> there a register in the processor or a setting in the IAR Embedded
> Workbench that I'm missing that would fix this problem?

Check under Linker settings, and verify "Buffered terminal output" is
unchecked. 


Joel