I2C addresses for MCP23017-E/SS chips are wrong.
In the current schematics file [0], the I2C addresses for MCP23017-E/SS chips are wrong.
According to A0, A1, A2 pins, the correct ones are:
IC1 -> 0x27
IC2 -> 0x24
IC3 -> 0x22
IC4 -> 0x26
IC5 -> 0x21
IC6 -> 0x25
[0] https://www.ohwr.org/project/fmc-conn-tester/blob/master/trunk/circuit_board/fmc_carrier_tester.pdf