Hobbyking F40A esc flashing

Hello, I’ve done some research but cannot find which fw I need to flash this esc with? It has the Atmega 8A chip with the numbers AU1223 on it. I have flashed several F20A’s and F30A’s with the bs-nfet.hex file under the V2013-05-15 fw, but have read that the F40A needs to be flashed with [...]