Posts made by hbang

@dc42
Thank you! I'll give this a try and let you know how it turns out.

@henrydara

Just to make sure all of the basics are occurring as expected:

Does M587 report the expected network?

Did you delete existing networks with M588 S"*", then re-enter your expected network using M587 S“mynetwork” P”mynetworkpassword” (making sure that the case of each is correct)? Note that attempts to overwrite the network setting with M587 doesn't seem to work unless you delete the old one first - but it sounds like you did.

When you enter M552 S1, the blue led should flash for a few seconds as it tries to connect. Then you should get a message back either saying that it is connected successfully with the IP address it obtained from DHCP reported, or you should get back a message saying that it failed to connect. Are you getting either message?

@elmoret Thank you.... you were right. There was a loose copper strand in the connector to the servo touching across power and ground and leading to a short.

(Using the Duet Wifi 1.0.4 board with 2.02 firmware)

I'm currently using the servo command M280 with the "S" argument using the microsecond timing option, giving values between 600 and 2400 microseconds to control a set of servos for a camera gimbal. However, I'm having trouble getting the level of accuracy I was hoping to achieve in pointing the camera.

It's not clear to me if this is a limitation of the servos, or whether the timing resolution of the pulse being sent by the Duet is small enough to allow the servo to move a very small distance. Right now the minimum change it takes approaches 20 microseconds. Changes less than that won't cause a movement.

I was hoping to get approximately 1 degree of resolution in movement. The servos are made to rotate nearly 400 degrees over the range of 600us to 2400us, so let's say each approximate degree of movement would require a change in pulse timing of 5us. However it appears I need a value change in the M280 S parameter of about 20us to see any movement, but this results in a movement of about 4 degrees.

What is the smallest resolution step possible with the M280 command using the microsecond pulse option? I'm currently using the P3, P4, and P5 options to control the servos through the heater outputs on the expansion board.

Thank you for any insight as to what I don't understand here.

On our Duet 3D v1.0.4 board, the chip at U3 went up in smoke and the text on it is no longer readable. It may have the label 4403T based upon photos of other boards.

Just a few seconds before the smoke we heard the Y axis dual steppers start oscillating as if jammed and couldn't get power killed fast enough to save it. We don't feel any jam in the motors or the tracks when turning the shafts by hand and there's no debris in the tracks to explain this. But we're not 100% sure if a motor stall caused the chip to fry or the stall/chatter was just a side effect of the chip failing. Which was cause and which was effect, in other words. We believe the motors themselves are properly compatible and everything has been working well for a few weeks before this.

Any ideas about what could cause this?

We have two additional backup boards on order for delivery tomorrow so we won't be down too long. We are having trouble clearly identifying this chip online (maybe it is 4403T-1432-883L?).

Does anyone think we could replace this with precision soldering equipment? Could there another failure related to this even if we did replace it?

Thank you for reading and for any help you can provide! We'd hate to put a new board in and fry it too.