Question on MESA boards config

Hello everyone,
I have a set-up consisting of a MESA 7i80-DB connected to two daughtercards, 7i76 for stepper motor control + a 7i85 additional board. I would like to add a third board, MESA 7i87, to read some analog sensors.
Do you know if this is possible or not? Is there a LinuxCNC firmware for this configuration?

Do double check this, but it should be possible to just wire the 7i87 to 7i76 using a cut off LAN cable, the Smart Serial connector, info on exact wiring is on the 7i76 manual.

Just did that and it seems possible. Now the next question, which bit file should i use for this configuration (7i80-DB + 7i85 and 7i76 with the 7i87 connected to the 7i76)? thank u

There's 7I76+7I85S firmware for a 7I80DB but not for the 7I76+7I85.
I can make this if you tell me which version of the 7I80DB you have (-16 or -25)

Note that Sserial cards don't need any card specific support in the firmware.
(as long as there is a sserial port, any sserial card is supported)

The 7I76 has 1 free sserial port and the 7I85 has 5 free sserial ports.

Ok if the card doesn't need any specific firmware, then it's fine, I already have the bit file for the other cards. Is there some specific settings i should add to the hal/ini files for it to work?

You _do_ need specific firmware for the 7I80DB with 7I76+7I85 daughtercards
If you have this, any serial card is supported.

In case you do not have 7I80DB 7I76_7I85 firmware, here it is: