PMDC SERVO MOTOR WITH quadrature encoder DRIVE ?

[Acetronics2]

Hi, Dave

For HSPLL Osc ...

I just run a 12 Mhz XTAL on a 18F4420, PLL Engaged ... everything fine.

So, May be the XTAL ... or may be your board layout ( 40 Mhz is HF !!! ) or ... poor quality capacitors.

Alain

[mackrackit]

Hi, Dave

For HSPLL Osc ...

I just run a 12 Mhz XTAL on a 18F4420, PLL Engaged ... everything fine.

So, May be the XTAL ... or may be your board layout ( 40 Mhz is HF !!! ) or ... poor quality capacitors.

Alain

I am using a resonator so maybe that is off a bit on the specs.

All this is on a bread board so maybe the problem is there but I have 4550s running at 48Mhz on same type of boards. Using the PicKit2 for the power supply. Maybe more caps across VSS/VDD is needed.

I got busy with something else so I have not had time to play with it lately. Still sitting on the bench... waiting...