As long as you have a valid backup of your original firmware, you can restore your C7 by following these instructions.
But, before you go any further, double check the contents of your backup at address 0x00001000 (like with a Hex Editor). If that byte contains 0xFF, then your backup is invalid and will brick your C7 again, so STOP! I will address this situation in another post soon.
OK now, first of all, you'll need the following gear:
1. A Bus Pirate
2. A Bus Pirate Probe cable
3. A Pomona 5250 SOIC Clip
Do not substitute the 3M part for the Pomona, as it won't work. The Bus Pirate is an inexpensive hacker's tool that can serve as an external chip programmer. It's supported by flashrom and although painfully slow, it does the job quite well. It all cost me ~$60 including shipping.
This presentation will provide a good step-by-step guide to disassembling your C7 to get access to the EEPROM which is on the top side of the motherboard
(MB), under the keyboard. It looks like a horrible nightmare, but thanks to these guys, it really isn't too difficult. However, I do recommend disconnecting both the keyboard and the trackpad, their cables and connectors are too fragile to risk leaving connected, IMHO. I will admit that reconnecting them is a royal PITA, though.
Here's an ASCII diagram detailing how to connect the Bus Pirate (BP) to the C7's EEPROM.
On my MB, the chip is a Macronix MX25L6406E, but yours might differ. You should also be aware that there's more than one probe cable design and the color schemes vary. I'm using the Seeed Studio probe cable design. For more info on the BP, consult:
For instructions on programming the EEPROM, consult this authority:
He's using a Samsung 550 Chromebook, but the procedure is the same. The C7's battery pack is, of course, removable. So, as long as the battery is disconnected, it's already "cut."