I'm using Configurable Firmata and Maxuino to control motors. Using an A4988 driver, everything works perfectly. However when I switch to the DRV8825 driver (which has a slightly different setup, with respect to where the Arduino 5V gets hooked into) nothing happens.
When i put the DRV8825 driver on a RepRap RAMPS 1.4 board, firmata is able to control it then. I'm not quite sure what the RAMP 1.4 board is doing that my breadboard layout isn't, but there seems to be something missing.
I've checked with a multimeter with my breadboard wiring, and it's getting proper voltage at both the voltage pins. Any ideas on what i'm overlooking?
So I was working on a large breadboard with two a4988's, and two drv8825's. the a4988's worked fine with the code/wiring, but both the drv8825's didn't.
i decided to narrow down the wiring and focus on a single drv8825. Now it's having some quirky behavior:
At times the motor will make some internal noises and I can send it signals to spin it, but other times it will go silent and won't respond to any signals i send it. These happen at fairly frequent and equal intervals. When it is on, the voltage at the motor supply pins read around 11.2V, but when it's off it's reading the full 12V (the power supply is 12V30A, and the driver has a minimum rating of 8.25V). When the motor is spinning the voltage reads around 11.7-11.8V.
Also as long as I keep it spinning, it works fine and doesn't shut off.
Any ideas on this behavior?
Thanks
---update---
ok, so this seems to be more of an issue with the drv8825, than anything to do with arduino/firmata. probably concerning current/voltage supply (my motor only needs 1.7A, which the driver can handle). I guess I can take this issue over to Pololu forums since it has to do with their product. A guy, who has the same issue as me, posted this two years ago http://forum.pololu.com/viewtopic.php?f=15&t=7324
GregFinger:
my connection diagram follows the one found on
...SNIP...
I can take a picture of my breadboard as well if you would like to check if I wired it correctly.
Neither is satisfactory. Make a pencil drawing showing how YOUR project is wired up and post a photo of the drawing. You may even discover the problem while you are making the drawing.
the code i'm using is the configurable firmata code found here
It will be a lot more convenient if you post the code in this Forum.
Make it as easy as possible for people to help you.
Robin2:
Neither is satisfactory. Make a pencil drawing showing how YOUR project is wired up and post a photo of the drawing. You may even discover the problem while you are making the drawing.
I found the problem and it had to do with my current supply. I think i was supplying too much current (i think the Vref measured around 1.6V, which the specs say thats delivering 3.2A...), because when i turned the trim pot to limit the current more (down to a Vref of above 1V), i could finally start driving the motors, which are rated at 2A. Does that make sense? I'm not really sure why a supply of too many amps would prevent the motor from spinning. I can understand that it would damage it, which thankfully it didn't.
It will be a lot more convenient if you post the code in this Forum.
Make it as easy as possible for people to help you.
Ok, noted for next time. Just wasn't sure how appropriate it was pasting 344 lines of code.