ABS Encoder Posital 7i92T bit file help

For just analog + enables a 7I83 is a good choice

Hi Peter, am I seeing this right? 7i92T P2 DB25 out to a 7i74 cat5 out to a 7i83.

The 7i74 has eight transmit -receive channels. One would be used by the 7i83 the rest for abs encoders. SSI needs data and clock signals. Would I get both data and clock with the remaining channels i.e. 7 abs encodes?

And to double up I would use P1 on 7i92T out to another 7i74 – 7i83

-Doug

Yes, a 7I74 provides 8 RS-422 channels, these can be
absolute encoder channels, sserial channels, etc
 

Wow, my head is spinning with the possibilities. I really need to get good at SSerial.

I ordered a 7i74 and a 7i83 should be in my hands tomorrow late afternoon.

Do i need to do anymore for you on pinouts? I'm thinking just mimic 7i77.

Thank you
-Doug

Let me see if a 7I92T config with two 7I74s (say 6 SSI + 2 SSerial each) fits

Edit, easily:

 

 

That is a great fit.
I'll give you and everyone an update when I get the boards in.

Thank you for all that you do, For everyone.

-Doug

Ok, here’s where I’m at.   7i74 and 7i70 all in and seem to be doing fine.   I am getting a ssi data-incomplete error and some other errors that seems to be clock related as well.  I've been studying the  SSI absolute encoders and analog servos - LinuxCNC  thread and I've attached several photos that were asked for in that thread as well as the readhmid output and of coarse the hal file.    I really chopped off  the hal file to keep it minimal, for the moment.  My plan is to use the Show Hal Configuration GUI  to verify that I have basic functionality.  I can see the SSI encoder pins in the HAL CONFIG GUI but the raw counts don’t change with shaft movements, and I have the data-incomplete read error.The loaner encoder from my distributor isn’t the exact model that I attached earlier. This version has an 8 pin barrel connector, it must have come out of a test setup.  I’m dealing with unmarked flying leads that I’ve had to beep out…hopefully I haven’t screwed anything up working the mirror image side.  I’ve also attached the RJ45 wire scheme that I used.   There’s plenty of room for errors between my chopped hal file and getting the right wire to the right pin.  The phase-lock loop error seems ominous, hopefully I just need to tweak the DPll parameters.-Doug
     

Comment out this line:

setp hm2_7i92.0.dpll.base-freq-khz 500

The DPLL base frequency is set automatically
(to the servo thread frequency)

Also the 49 ms latency is _really_ bad so suggests a real time issue with the host
(maybe you don't have
Disabling the base thread in the latency-histogram may give you better results:

latency-histogram --nobase --sbinsize 1000

 

Yep, that fixed the data incomplete error and the phase lock error.  Still no change to rawcounts with shaft movements.   Probably time to start swapping data and clock wires.... Is there a way to use Hal Scope to view the data and clock stream?    I have an o-scope too.  I'm mostly fumble around with it though.