trouble shoting "Pin 'hm2_5i25.0.7i76.0.0.input-24' does not exist 4977"

7i92_7i76x1D.bit

DB25
1 & 14
2 & 15
3 & 16
4 & 17, etc....

This Pinout tested Success for:
Yes 5V Cable Power 7i92 to 7i76

Yes Both Power LED are ON.
CR1 5V Cable Power from 7i92
CR2 24V Field to VIN

Tested Fail for:
Same problem Motors won't turn, Limit Switches fail to compile...
hm2_7i92.0.7i76.0.0.input-oo "does not exist"

Fail yet unknown
although CR1 & CR2 ON & yes 7i92 5V Cable Power @ 7i76D.

Again, a correctly made IDC cable is all that's required .
(as long as you have IDC-HDR26 pin1 to IDC-DB25 pin 1, its correct)

A hand soldered cable can certainly be wrong however.

For the 7I76 to work with the 7I92, you need:

1. 7I92 with 7I76 firmware installed (verify with mesaflash --readhmid option)
2. 7I76 connected to primary 7I92 connector (P2) with proper (pin 1 to pin 1, IDC) cable
3. 7I76 has both 5V and field power supplied (and W1 left)
4 7I76 W3 left (operate mode)

.

In the photo above the IDC26 Female Cable #1 Pin is on Left when looking at the connector from facing side.

In 7i92 Manual Schematic, P2 I/O 0..16
are ordered bottom to top 0 to 16. or IDC26 Left to Right.
Schematic indicates P2 IDC26 #1 Pin is on the Bottom or IDC26 = Left is Pin#1.

None of that is relevant, It's as simple as this:

If you have IDC connectors and you align pin1 to pin 1, the cable is correct.

.