Amt212b-v encoder not working

1

Hi Guys,

I’m using oDrive motor controller for an experimental setup in my research project. I’m using T-Motor P80 III Kv 120 motor with AMT212B-V absolute encoder.

I having a serious issue with this encoder. The wiring of the encoder looks fine, but the output for “odrv0.axis1.encoder.shadow_count” is always 0 though I turn the motor. I have set the encoder cpr to 16384 (14bit resolution) but I’m not getting any output.

However, I checked the encoder, using AMT viewpoint software, it works perfectly.

Could anyone please help me in getting this encoder works with oDrive motor controller.

Thanks.

2

Can you check that the CS GPIO pin is configured correctly? Do you have a scope to see if it is being set?

3

This appears to be an RS-485 encoder? ODrive currently only supports incremental or SSI absolute encoders. https://www.cuidevices.com/product/resource/amt21.pdf

How did you hook it up? You say the wiring looks right but we don’t even have anywhere to plug this in lol

image

4

@Wetmelon Ohh really, didn’t know that the encoder interface not supported with oDrive. I thought AB connection would work as this encoder was listed in the encoder guide ( https://docs.google.com/spreadsheets/d/1OBDwYrBb5zUPZLrhL98ezZbg94tUsZcdTuwiVNgVqpU/edit#gid=0)
Do you have any idea how I can use this AMT 21 encoder with oDrive ?

5

@towen I think, according to @Wetmelon this encoder not supported for odrive.

6

yes, i had assumed this was one of the SPI encoders.
The RS485 will not work. Maybe you can use the AB incremental interface only, but it will not be very useful on its own. you’ll need a full calibration on each boot up