I've recently designed a FPGA breakout board using an FPGA BGA package, and due to the lack of packages I had on hand, I got the BGA-256 and drew new symbols and updated the connections from scratch.
Everything was spot on until I started drawing the schematic - upon a quick spot check to the PCB layout, my one BGA had turned into two identically-oriented packages with identical airwires as well as identical pin consolidation within the BGA array.
Any ideas on how to correct this issue? I cannot delete the duplicate part because if I do, I receive the "No forward-/backward-annotation can be performed!" error. Here's the schematic:
Board with "cloned" device:
So, what I was trying to do is put two pairs (four FPGAs) of FPGAs together for bitcoin mining onto a DIMM-form card that can "hot socket" into a multi-socket backplane/motherboard that carries the I/O and interface devices.
To save space and prevent from cluttering the schematic excessively, I decided to only connect pins that I determined were needed for my setup, namely the configuration and power pins and certain pins from I/O banks 0 to 3. Mapping these pins would also give me a much clearer view upon routing.
This is why the FPGA symbol in the schematic is multi-grouped and not a standard shape or size. The larger symbol to the left is a representation of the DIMM edge connector that I will build these FPGAs to. The only connection I have made at the point of screen capturing was to tie low all appropriate grounding points on the edge connector and FPGA ballout.
At first glance, because I stated I was using two pairs, having second copies may seem to make my life easier; but instead of having two pairs in parallel, I would have two doing the exact same thing.