SSI ABS Encoder

andypugh wrote: counts-per-rev should probably be 4096. But that isn't the problem.

Setting it to a much larger number might be an interesting experiment, though.

Is there any way to see the raw data from the encoder? if no-wrap is active then the driver doesn't do very much with the data that comes back. Is it possible that what you see is the actual numbers from the encoder?

I think you can use "enable_raw" in the loadrt hostmot2 line of the hal and peek at the actual register values on the FPGA.

linuxcnc.org/docs/2.8/html/man/man9/hostmot2.9.html#Raw%20Mode

I have attached the hostmot2 register map so that you know where to look.

andypugh wrote: Specifically this bit..

Code:

SSI Data Register0, right justifed. Writes to this location will start a read cycle for the specific SSI interface addressed 0x6900 SSI data register0 channel 0 0x6904 SSI data register0 channel 1 0x6908 SSI data register0 channel 2 0x690C SSI data register0 channel 3 ... 0x6A00 SSI data register1 channel 0 0x6A04 SSI data register1 channel 1 0x6A08 SSI data register1 channel 2 0x6A0C SSI data register1 channel 3

PCW wrote: What does hm2_7i80.0.ssi.00.zencoder.rawcounts
show?

it shows from 0-4096
But when I restart linux cnc, the values (3072 to 4096 ) is negative numbers from -1024 ->-1

annhandt09 wrote: The values return from 0x0000000->0x0000ffff for 0->4096