\xcd\x03\x800\x01v\xd5\x07\xfe@\xe8\x0f
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 DE ;0006 D5 . RLCA ;0007 07 . CP 040H ;0008 FE 40 . @ RET PE ;000A E8 . RRCA ;000B 0F .