\xd5\x00\xcd\x03\x808\x03\xfe#8v\x08#~\xb7 \x03.\x1d~\x08 \x04\x08\xee \x08\x08\x18helloworld
Note that non-ascii characters in the above source code will be escaped (such as \x9f).
Disassemble:
ORG 00000H PUSH DE ;0000 D5 . NOP ;0001 00 . CALL 08003H ;0002 CD 03 80 . . . JR C,$+5 ;0005 38 03 8 . CP 023H ;0007 FE 23 . # JR C,$+120 ;0009 38 76 8 V EX AF,AF' ;000B 08 . INC HL ;000C 23 # LD A,(HL) ;000D 7E ~ OR A ;000E B7 . JR NZ,$+5 ;000F 20 03 . LD L,01DH ;0011 2E 1D . . LD A,(HL) ;0013 7E ~ EX AF,AF' ;0014 08 . JR NZ,$+6 ;0015 20 04 . EX AF,AF' ;0017 08 . XOR 020H ;0018 EE 20 . EX AF,AF' ;001A 08 . EX AF,AF' ;001B 08 . JR $+106 ;001C 18 68 . H LD H,L ;001E 65 E LD L,H ;001F 6C L LD L,H ;0020 6C L LD L,A ;0021 6F O LD (HL),A ;0022 77 W LD L,A ;0023 6F O LD (HL),D ;0024 72 R LD L,H ;0025 6C L LD H,H ;0026 64 D