Electrical system malfunction

I went to start the car, and had voltage, but it would not crank. I hooked up a battery pack backwards (neg on pos) and tried to start. No voltage in electrical system. Battery still has voltage.

Trying to determine what may be damaged, due to crossed wires, i.e., ECM,ICM,fusible link, etc. When I first tried starting, I had door chime. After hooking battery pack, no electrical whatsoever.

Thank you in advance.

Rick Gossett