CYCLON IV GX - ALTGX Won't recieve any valid data

Hey dave, so we tested the new code, now sending f0 to get a slow repeating signal and yet we still can't get a freq_locked signal.

it seems that it is a physical problem after all..., we have no way to be certain since the signal seems fine.

the bigger problem is we can't ac couple the signal since the board is already built, unless there is some way to do it.

the other thing is that we disabled Rref so we can't use internal termination since it has no refference resistors.

is there anything we can do?