Lpc2000

At 12:25 AM 4/29/2006 +0000, jayasooriah wrote:
>--- In lpc2000@yahoogroups.com, Robert Adsett <subscriptions@...>
>
> > It really stinks of an underlying HW race
> > condition.
>
>I think the kind hardware *and* software (in the supplied Bootloader)
>problems on the LPC Family is without precedent.

I've seen worse, and I've heard that the 4 bit micros used in are much 
worse.  At least all the problems are in the peripherals and most have SW 
workarounds.  Race conditions seem to have been a particular blind spot for 
some reason though, most of the HW problems seem to lead back to some sort 
of race.

>The software problems -- implementation of boot loader ISP mode pin
>function clashes with DCD requirements when UART0 is used in slave
>mode; boot loader external bus select implementation clashes with use
>of analog inputs, how it attempts to provide security, how it
>interfaces with the outside world.

DCD/ISP is a design issue not a SW or HW bug.  Personally I don't think the 
ISP pin should have bee multiplexed at all but other micros do similar 
things with similar consequences if the data sheets are not read carefully 
and the startup conditions fully considered.

>Never have I see so much discussion about hardware solutions to
>software problems as much as I have in this forum.

Um, hardware solutions to software problems, what hardware solutions to 
what software problems?  I haven't seen any discussed.  The closest I've 
seen was a use of an or gate for allowing DCD to be used (a single sot23 
for an extra input pin, not a bad tradeoff). I'd consider that a hardware 
solution to a design problem, possibly a hardware solution to a hardware 
problem.  The user manual should be more open about the dangers of DCD 
though to warn off the unwary.

Despite the fact I'd like to see Philips being a little faster about 
acknowledging bugs they do at least make the errata easily available.

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
http://www.aeolusdevelopment.com/