Changes

Dk'tronics Lightpen

2 bytes removed, 20:56, 2 March 2010
/* Software */
* Text Menu - Vertical Text / Horizontal Text / Set Colour
* Scratch Pad - Screen to Pad / Edit / Pad to Screen
 
Rubber Band was a method of drawing curves and irregular shapes by defining points on the screen to be joined by a line.
The handbook also gave instructions in both BASIC and assembly to use the lightpen within your own programs. A small routine to return the X and Y coordinates which worked in all screen modes:
  10 out &1C00, 17 : L=inp(&1F00) : out &1C00, 16 : H=inp(&1F00)  20 L=H*256+L-12292 : Y=L/40 : X=L-Y*40 
The value 12292 needed to be slightly adjusted to match the monitor being used. This could also be achieved in software by incorporating a simple manual calibration routine.
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