/JAM ether by continuous transmission

loc 16_1000

l1:
  ld c,2         /DMA(ET) count
  ld hl,buf
  out (c),hl
  inc c
  ld hl,16_9FFF  / 8kbytes (+16_8000-1)
  out (c),hl
  ld a,16_42     /TCstop+ET
  out (8),a
l2:
  in a,(16_60)   /Ether status
  and 16_a0      /Collision and Done bits
  jr z,l2
  jp p,l3        /No collision ->
  out (16_60),a  /Reset transmitter
l3:
  xor a          /Reset DMA
  out (8),a
  jr l1
  ld hl,0        /Delay
l4: inc hl
  ld a,l; or h; jr nz,l4
  jr l1

buf: 1; 2
  3; 4; 5; 6
  7; 8
  9; 10; 11; 12
  1; 1

end