Added PVs for synchronizing motor home with a PandA

[LuisFSegalla]

implements #149.

[LuisFSegalla]

Just wanted to point out that while testing this against real hardware I wasn't able to see any changes in the PandA after a successful homing routine. My initial thought was that due to the PandA IOC that I was using being based in FastCS, which uses PVAccess instead of ChannelAcess this might be causing some conflict that leads to the PandA PVs not updating with the correct values. Any thoughts on this @coretl?

[coretl]

I think it does both CA and PVA, so that shouldn't affect it. Could you try putting TPRO on the records to check they are processing correctly? And if you camonitor ...Inenc1:Setp then does it change?

[LuisFSegalla]

Adding the TPRO field was very helpful and I could confirm that the PVs created are being processed in the correct order. I tried doing a pvmonitor on the ...Inenc1:Setp PV but I can't see any changes on it (or in any of the other PVs that we're supposed to update after the homing routine.

[coretl]

Hmm, you could try pointing the output at a different record than Setp, maybe something local to the PMAC IOC, to see if that gets updated?

[LuisFSegalla]

For testing purposes I changed the output of the :SETPOSCALC PV to be $(MOTOR).RTRY. If I change the number of retries and then run a homing routine I can see that after the routine is done all the PVs update and and .RTRY is updated to 0 (this makes sense due to the value of $(MOTOR).REP).
Something I noticed is that even thought the set PVs work for the PandA IOC, I can't see the readback from it. The _RBV values don't seem to update accordingly with the changes send to the controller.