[mick22]

Hi Mick,
You say you have torque in one direction only. Is it completely "dead" in the other direction or do you have "some" torque but not as much as in the first direction?

I ask because I've expereinced both problems... ;-) At first I had no torque at all in one direction, this turned out to be a fabrication error on the PCB which resulted in the gate-drive signals being shorted to ground for one of the MOSFETs. There's more info in the old thread.

Then I had the problem with different torque depending on direction and this was cuased by the current limit circuit triggering due to noice, increasing C29 from 100pF to 470pF cured it on my test drive.

If you have a scope, look at the PWM output from the UHU-processor to see if it "tries" to apply torque in both directions, then look at the outputs from both IR21844 driver chips and see if you have drive signals to the MOSFETs.

HTH
/Henrik.

hello Henrik,
no it is not completely dead, infact it is possible to get torque in
both directions,but not when the settings have been adjusted to make the
rotor stop after a reset.

i have had a situation where reseting toggles the direction of rotation.

no i dont have a scope.
thanks, mick
Henrik,
there are no step and dir signals connected yet,could this have
anything to do with it.
regards.