Lpc2000

Just out of curiosity, is your ISP programming baud rate within the 
specified range?

I know with a 14.7456 Mhz Xtal you can get any ISP programming baud 
you want (9600 - 230000). However at 20MHz it's probably unsafe to 
go over 38400.




--- In lpc2000@yahoogroups.com, MaxStream - Ryan Bedwell 
<ryanb@m...> wrote:
> Robert Adsett wrote:
> 
> > You are in range of all the PLL specs?  I've seen the micro 
operate but 
> > some peripherals fail when Fcco was out of the specified range 
and cclk was 
> > within the specified range.
> 
> Yes, everything looks good to me:
> 
> Fosc = 20 MHz
> Cclk = 60 MHz
> M = 3
> P = 2
> Fcco = 240 MHz
> 
> To make matters worse (or perhaps more interesting), I've now seen 
some 
> processors which fail flash programming via ISP or JTAG at 20 MHz, 
but 
> work with a lower clock (15 or 10 MHz, depending on the part).  
I've got 
> a device which I successfully programmed with my code (written for 
60 
> MHz CCLK operation with a 20 MHz crystal), using a 10 MHz clock 
for the 
> flash programming.  I then could run the code fine with the 20 MHz 
> clock.  However, anytime I try to program this unit's flash via 
IAP with 
> the 20 MHz clock -- even with the PLL off -- the Philips code 
again 
> seems to get lost in space.  Most of the other parts I've seen the 
> problem with were fine @ 20 MHz with the PLL disconnected.
> 
> I was following the oscillator discussion a few days ago... 
however we 
> don't think that's the problem because we've taken to using a 
> capacitively coupled signal generator for our latest tests.
> 
> Ryan