Mesa smart serial or PktUART or serial over RS232 or udp for robot joints

It's good thing to know.
Do you know are there some configs with stmbl driving robots available around?
I saw some integrations with robots but encoders are read by mesa cards directly.
I would be more interested in this part which you mentioned if stmbls are set up in this way that they send position over smart serial.

Do you happen to know on higher level how this position report over smart serial works if we want to read 6 robot joints positions?
Correct me if I am wrong, but possibly in HAL we would have 6 sequential position requests, one request per each joint. We would wait for each one stmbl to report its position. So request + stmbl processing time + reply over smart serial and this happens 6 times. From fast look earlier not 100% sure but I think that there are 2 mcu in stmbl, so possibly one of them fast handles communication.

As I know, you can use a smart serial UART to read the Yaskawa ABS encoder, but you need to make a custom component to handle it, including 2 elements: a UART channel and an increment encoder channel.
1st: read the ABS encoder at the initial state
2nd: set the abs position by summing up the abs and increment

Okey, are you referring to make custom firmware/component for FPGA for UART + quadrature encoder logic or referring to hal component?

Just a hal component to take data from the UART and encoder channel then handle it

There is an example .comp here:

github.com/LinuxCNC/linuxcnc/blob/master...ivers/mesa_uart.comp

Or if the PktUART is a better fit (it probably is) have a look at:
github.com/LinuxCNC/linuxcnc/blob/master...sa_pktgyro_test.comp

Thanks both on suggestions, I see, checked both links quickly.
Have a question on principal level.
I need to have in fpga both uart component and quadrature enc component.
In order to work enc reading, first enc input pins should be connected to fpga input uart pins and then via some logic/demux this pins needs to be routed to quadrature logic in order to get inc pulses and also there is need to issue select signals on this demux after uart transfer sequence is finished.
Or other way, enc pins are connected to both uart and quadrature module components inside fpga but enable signals of both components are separately controlled via some conditions/logic.
Is this working this way or?

Actually I took a look at this in the past and had some example firmware source, I will take a look on Monday.
And yes, it requires grafting on a simple UART connected to the "A" encoder pin (the UART can be quite basic as its
parameters are fixed)
 

Great, in meantime I am wondering, rough estimation could it be all logic (6x uart + quadrature logic + 6 to 8 stepgens + 1 smart serial) packed to 6i25 or 7i92?
I think that I don't need C signal from encoder to count full revolutions.
Yes uart parameters are fixed.
I am seeing the next sequence, LinuxCNC will issue power up of servo drivers and encoders would be connected both to drivers and RS422 to TTL converters (encoders are RS422), so there would be 2 listeners per encoder on RS422 network (think this should not be a problem for RS422).
Drivers will issue power on for encoders and this is trigger for them to send data.
After RS422 -> TTL conversion then will be signal isolation and then fpga.

I have looked on availbale logic and its signals.
So could it work if firmware is made from regular configuration for a test to have one quadrature encoder and one uart, and I could tight pins together outside of fpga.
Think that only A line is used for uart.
So both components will recieve uart data and then after uart is recieved I could just flush/reset/set to zero quadrature encoder pulse accumulator and continue from this state.
Would this work?

Don't neglect the possibility of simply connecting the same physical wire to both a uart and and encoder phase.