\xcd\x03\x800\x01v\xc5o\xf9\xc3
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 NC,$+3 ;0003 30 01 0 . HALT ;0005 76 V PUSH BC ;0006 C5 . LD L,A ;0007 6F O LD SP,HL ;0008 F9 . DEFB 0C3H ;0009 C3 .