opt o+ h+ ?+

EOL = 155

ICCMD = $342
ICBUFA = $344
ICBUFL = $348

PUTBT = %1011
JCIOV = $e456

  org $600

  ldx #0
  lda #PUTBT
  sta ICCMD,x
  lda #<hw
  sta ICBUFA,x
  lda #>hw
  sta ICBUFA+1,x
  lda #<hw.?len
  sta ICBUFL,x
  lda #>hw.?len
  sta ICBUFL+1,x
  jsr JCIOV

  jmp *

hw .db 'Hello World!',EOL
?len = *-hw

  run $600

  end