Single signal Encoder with Beagle Bone blue

General Discussion
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Hey All, I am trying to use this single input rotary encoder : Hobby Motor and Encoder Kit - ROB-13260 - SparkFun Electronics
on the beagle bone blue, I am aware the BBBL uses two signals for the eQEP modules, I am currently routing the signal B to VCC and it is giving me mixed results usually has low resolution and won’t count when more than both wheels are running. I am using Debian 9 and RC version 1.0.4.
Is there a better way of using a single input encoder?

1 Like
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Hmm.

Encoder. I say hardwire your own but the 6v motor should suit your needs and the source used should work for encoder in/out. I say that without testing.

I am not sure how equipped you are currently but…

  1. I noticed on the BBB with Bullseye Debian 11, the eQEP modules are listed in /dev/bone/ (I think).
  2. I am testing now. Stick with me on this experiment.
  3. cat /etc/dogtag: BeagleBoard.org Debian Bullseye IoT Image 2023-04-12
  4. uname -a: Linux BeagleBone 5.10.168-ti-r75 #1bullseye SMP PREEMPT Thu Dec 28 22:52:21 UTC 2023 armv7l GNU/Linux

Okay, so. I am in my system now with the above credentials/firmware/image/kernel.

I think they are called counter in /dev/bone/. I will need to check further…

Seth

P.S. But…one could use a driver instead of the BBBlue and driver onboard for another type of motor. I know this is redirecting you here. I am actually trying to redirect you. Just for reference, I know very little of the source for the libroboticscontrol lib. or RC version 1.0.4.

I know the latest-greatest is 1.0.5 (I think). I could be outdated. I hate to say this but… I may not be able to supply directions or even a direct answer because of the Debian 9 versioning being a bit older. If it works…awesome. Do not change it.

Where are the files for eQEP coding and source usage located on your current image and kernel? Blunt questioning here but I think it may provide some answers.

Anyway…the motor drivers to use for the BBB would be something simple like a L298 driver or another type that is readily available. If you are stuck on Debian Stretch (9) for usage, I might be out of ideas.

I am sure there are ready made drivers for encoding types that play nice with the am335x which beagleboard.org does support currently. There is a lot of data now on the am335x and BBBlue SiP. Hard to find, yes sir. Easy to mess up, even easier. I see docs.beagleboard.org has some newer ideas for the librobotcontrol library.

Update

Look here first:

https://docs.beagleboard.org/latest/projects/librobotcontrol/docs/index.html

3

https://adafruit-beaglebone-io-python.readthedocs.io/en/latest/Encoder.html

This may help too.

I am not sure how you are programming things or if you are only using the lib.

CUI Devices had a specific motor a while back that was generally used back then for 6v type encoder usage. Here: https://www.mouser.com/datasheet/2/670/amt10-2298320.pdf

I know this is something to take in now. As you can tell, I am new to librobotcontrol. Sorry for the first link from my previous post. I was unaware of what beagleboard.org people were doing with the branch main.

Seth

Update try to disable video in /boot/uEnv.txt

…

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You can enable the eQEP direction-count mode, see page 2544 in the TRM (SPRUH73Q).

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I keep trying to set the mode of the direction-code to 2 (count up in single mode) put it just keeps reseting itself to 0

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The eQEP feature in libpruio allows to configure one, two or three input lines.

Regards

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You must either describe more in detail what you are doing
or you could follow the instructions in this example:

The Sparkfun motor kit you used is also used there!

To enable count-direction mode from PRU:
PWMSS1.EQEP_QDECCTL = 0x4000;