Lpc2000

From: <aff@...>
> The link is http://www.keil.com/mcb2130/mcb2130-schematics.pdf

Thanks.

WHAAATT? I expect the resistor between the output of the oscillator and the
connection of the crystal with the 22 pF capacitor (assuming RTXC2 is the
output, it should be on the left of C19, not on the right side). The way
shown it DECREASES the Q (resonance quality) of the crystal - and
oscillation is not likely. In series with the output it lowers the drive and
INCREASES the Q. This is a strange circuit indeed - and I expect a drawing
error...

The usual circuit  is (see in fixed font!):

    --------------------
   |                    |
   | |\                 |
    -| >o-- R ----- X --|
     |/         |       |
                C       C
                |       |
      GND ---------------

> I understand that in this case the resistor was used for limiting the
drive.
> I will take your suggestion about the value. (220K)

Start with my circuit with R is 560K - if the Keil circuit works at all,
that should be OK. If it does not start, try lower values. Don't go below
220K.

Regards,
Arie de Muynck