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# Z80 Assembler, 50 bytes

```z80asm
org 256
ld de,m
ld c,9
jp 5
m:db"Hello, world!\r$"
```

With assembler there's usually the problem which machine or operating system the program is for. I've chosen CP/M here as it runs on a variety of different machines with a Z80 processor.

CP/M programs start at address 0x100, but the decimal representation 256 is shorter.

The program loads the address of the $-terminated string into the D & E register pair, then the number of the print text subroutine (9) into the C register, and jumps to the BDOS entry.  It uses the `RET`urn of that routine to end itself, instead of `CALL`ing the BDOS and needing an own `RET` instruction in the program.