>!\x06\xf8\xcd\x00\x80\x10\xfbv
Note that non-ascii characters in the above source code will be escaped (such as \x9f).
Disassemble:
ORG 00000H LD A,021H ;0000 3E 21 > ! LD B,0F8H ;0002 06 F8 . . CALL 08000H ;0004 CD 00 80 . . . DJNZ $-3 ;0007 10 FB . . HALT ;0009 76 V