gen 3 motherboard...is it fried?

Hi to all on the forum,

Could any RepRappers out the help with the following problem?

I recently changed a fried extruder stepper driver connected to my gen 3 electronics. As the new stepper was 1/8th steps, I changed the firmware on the motherboard and tested it, all was well.

I then tried to get a quick test print done but before I had the chance to, the motherboard stopped working.

I checked the power supply and the stepper drivers for the axis were all lot up and ready for action, as was the extruder controller, however the motherboard is not working, no lights, not even the debug light?

I have checked the USB/ttl cable and it works.
The power supply also works.

Is the motherboard dead?

Possible Causes....

FDTI chip? I can't connect to my laptop even though the cable works.

With regards to the firmware change, I only changed the Esteps per mm parameter from 1372.7 to 686.35.


could this have caused the problem?

Update - No it wasn't,

On very close inspection i found a strand of copper wire which had fallen in between the the 644p chip and the pcb board which was causing the problem. I fishe this out with a sewing pin and the board worked.

With every positive though there seems to be two negatives as my (working yesterday) extruder stepper driver circuit is now not working. I bought two of these drivers and even replacing chip does not seem to sort it.

always the way....

Thanks

Raj

The short caused by the strand of copper may have burnt out one of the atmega pins used by the extruder.

---

FFF Settings Calculator	Gcode post processors	Geometric Object Deposition Tool Blog
Tantillus.org	Mini Printable Lathe	How NOT to install a Pololu driver

depending on the frmware use, you can move over to anther set of pins. i think there are some analog pins unused, that can be made digital pins. some where here is the schematic [reprap.org]

Hi,

There doesn't appear to have been any shorts causes by the bridge. I tried the extruder with astepper from a different printer and it does power up and move. I put another post up to try and find out why the new stepper I put together stopped working, even though I hadn't made any modifications to the machines setup.

Most likely a(nother) blown driver but a little annoying as it was working.


Thanks,

Raj