Discovery boot fail

[Awalkerch750]

As I powered up my EFIS it continued to load and load until I got this on the screen;

Loading Discovery from internal
Boot Fail code: 3
MCI card detected
External SC mounted Program EXP3; Bin from SD
File error: EXP3 . BIN
File header error: M-L238
SD does not have EXP3.EXB system
SD does not have U-BOOT .BIN
SD does not have MLO
Cannot find a system to load

How do I get my screen to come back. Was working fine. My battery did go dead for a while till I went out to the plane and discovered it.
Thanks; Allen