\xcd\x03\x808\x05\xe5\x04\xcb@\xccv
Note that non-ascii characters in the above source code will be escaped (such as \x9f).
Disassemble:
ORG 00000H CALL 08003H ;0000 CD 03 80 . . . JR C,$+7 ;0003 38 05 8 . PUSH HL ;0005 E5 . INC B ;0006 04 . BIT 0,B ;0007 CB 40 . @ DEFB 0CCH,076H ;0009 CC 76 . V