ZX Printer

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The ZX Printer prints on a roll of special metallised paper; it has a stylus which passes an electric current through the paper and blackens the surface.

It responds on any port with A2 set low.

  Bit
7 6 5 4 3 2 1 0
Read Paper start latch 0 1 1 1 1 1 Next pixel latch
Write Stylus power Motor Power Motor speed
  • Paper start latch: raised when the stylus reaches the start of the paper, or when stylus power is turned on.
  • Next pixel latch: raised when the stylus reaches the next pixel (approximately every 250 T-states when motor fast)
  • Stylus power: 0=off, 1=on
  • Motor power: 0=run, 1=stop
  • Motor speed: 0=fast, 1=slow (no effect if motor stopped)

Any I/O write to the printer also resets the latched signals.

BASIC commands

  • COPY (Z) will print the current screen (pixel data only; the state of attributes is ignored, so you might get some bits of your picture inverted).
  • LPRINT (Extend-C) acts like PRINT but sends output to the printer.
  • LLIST (Extend-V) acts like LIST.