Using 34 bit Biss-C sensor with SimuCUBE


#1

Hi,
while trying to configure my IONI drive with Granity, I noticed that the sum of single-turn and multi-turn bits is limited to 32 bits. The feedback device I am using is a RoboDrive RD85-AKSIM with Biss-C interface which has 18 bit single-turn resolution and 16 bit multi-turn resolution. When I put 18 bits for single-turn and 14 bits for multi-turn resolution in Granity and then test the settings as described here: https://granitedevices.com/wiki/Configuring_IONI_drive_in_SimuCUBE
at “Testing settings”, the motor holds position and has “bumps” if forced to turn. I tried inverting FBI and the value for MPC is definitely correct. So I assume that the missing 2 bits of multi-turn resolution could be the problem? Is there any way to make this encoder work properly?
Kind regards


#2

Similar things was discussed here:

Maybe @Tero can help on how to configure this encoder.


#3

Multiturn data is transmitted first from BiSS encoder so it’s not possible to avoid reading all bits of it. So you may try to set MT=16 and ST=16 bits as workaround. Let us know if that works!


#4

Setting MT=16 and ST=16 didn’t work either. However, I now made it work setting ST=21 and MT=11. I noticed that turning the wheel 90° made the virtual wheel in SimuCUBE configuration tool turn 720°, so there was kind of a transmission ratio of 8, although I am not using a gear. Adding 3 bits (=8) to ST did the trick.