Lpc2000

--- In lpc2000@yahoogroups.com, "rtstofer" <rstofer@p...> wrote:
>
> I have spent literally hours searching the Philips web site for 
> documentation other than the User Manual for the LPC2106 and a few app 
> notes.
> 
> Is there a document that has the electrical and timing specs for this 
> chip?
> 
> One reason I am curious is that I don't seem to be able to get very 
> short output pulses when I wiggle a pin.  Something on the order of 
> 100 nS is about the shortest I can get.  Now, I am running at 4x 
> 14.7456 MHz (I think!) and the VPBDIV is set to 0x01.  It would seem 
> that, at 59 MHz, I should be able to get very short pulses.
> 
> This isn't a problem, just a curiousity.  But, I would like to review 
> the specs.
> 
> Thanks
> Richard
>

Richard,

the timing specs are in the Data Sheet but this does not include pin
toggeling speeds. The LPC2106 can toggle with approx. 4 MHz at full
speed. 
THe newest device, the LPC2148 has the pins connected to with paths to
both busses, the APB (the docu calls it VPB) as slow as it was before
but compatible to existing software while the is a chapter in the
Users Manual how to toggle the pins faster, up to 15 MHz, which is the
fastest theoretically possible through software. 

afaik, the upcoming LPC2101/2/3 also have the fast toggle option. If
you are just looking for a micro that toggles a pin as fast as
possible, there are 8-bits that can do this as good as an ARM for
less, if you need speed for algorithms, do yourself a favor and forget
about 8-bit

hth, Bob