Lpc2000

* acetoel <acetoel@...>:
> But really, is there any difference if I use a 20Mhz crystal 
> oscilator than a 10Mhz?

Aside from the baud rate, there is another
difference between selecting a 10MHz and 20MHz
crystal; a reason very specific to the LPC2000
parts that have an older version of the bootloader
software.

Versions before 1.63 (I think, but check Philips'
site for the exact version) of the bootloader
software fail about 10% of the time when
programming the internal Flash when cclk is higher
than about 12-15MHz.

To work around this problem, simply disable the
PLL and work straight off the crystal frequency
while programming the Flash. That is, if your
crystal is below 12MHz. Otherwise, there is no way
to slow down the system enough to program without
error for that 1 part in 10.

Of course, you could simply update the bootloader
with a fixed version (provided by Philips on their
site and uploadable in the part using the Flash
utility), but sometimes this is not practicable.