Lpc2000

Clarification for possible clocks into the LPC2000 family, applies to
all devices. 

The input to the crystal oscillator can be any frequency from 1-30 MHz. 
The input from the crystal oscillator into the PLL has to be in the
range of 10-15 MHz (hence the spec). 
The ISP program needs the 10 MHz to function properly  but a
modification of the other source file, refered to as Maurer's code
might make it work.

So to exclude any doubts, it is possible to run the LPC2xxx devices at
3.6864 MHz but you can not use the PLL!

Our recommendation for frequencies outside the "mainstream
applications", use a JTAG debugger  that supports programming such as
Ashling, ARM, Nohau, Hitex, Keil, IAR. Hope I did not forget anyone. 

Will be more clear in future User's Manuals, my apologies, Robert

--- In lpc2000@yahoogroups.com, Robert Adsett <subscriptions@a...> wrote:
> At 01:01 AM 8/12/04 -0500, you wrote:
> >There might be some way to trick the bootloader and the chip into
> >programming the Flash.  Perhaps the Flash time periods would then be
> >off.  It might still work.
> >
> >I think the source is available for Maurer's bootloader, so if it does
> >set the serial speed, we might be able to change it to set it to one
> >quarter of what it will tell the LPC chip.
> 
> I think you misunderstood.  The 10MHz limit is listed as the minimum 
> operating frequency (for all conditions) not a minimum programming 
> frequency.  I'd expect most chips would work at least a little below
that 
> but more than a factor of 2 is probably wishful thinking.
> 
> There are other small ARMs that will work with lower frequency
inputs (The 
> AD parts come to mind).
> 
> Robert
> 
> 
> " 'Freedom' has no meaning of itself.  There are always restrictions,
> be they legal, genetic, or physical.  If you don't believe me, try to
> chew a radio signal. "
> 
>                          Kelvin Throop, III