Guru
Joined: 28/05/2012
Location: GermanyPosts: 1141
| Posted: 07:39pm 02 Jan 2022 |
...stupid question: Am I the only one who misses the oscillator???
From "CMM2_G1_Construction Guide.pdf":
External Oscillator
The latest PCB has provision for an external 8 MHz crystal oscillator to replace the 8 MHz crystal on the Waveshare CPU board. This may be needed in some rare cases where a monitor has difficulty with some VGA modes (such as 800x600 pixel 16-bit colour).
Most people will not need this modification however, if it is required, it can be implemented by installing the external oscillator and a capacitor on the motherboard (under the Waveshare CPU board). The 8MHz crystal on the Waveshare board does not have to be removed.
The parts required are:
1 SMD 1206 100nF ceramic capacitor
1 8MHz oscillator in 5.0 x 7.0 mm SMD package (QX7 XO 25ppm). Eg, RS Stock Nbr 813-6194.
Frank