Plus-X Terminator Laser Programming
This page was last modified 02:21, 7 October 2016 by Gdx.

Programming under BASIC

This is pretty easy device to program:

When ASCII Plus-X Terminator Laser is connected to joystick port 1 you can read it's status with BASIC commands STRIG(1) and STRIG(3)

  • STRIG(1)=-1 when ASCII Plus-X Terminator Laser is pointing to black pixel
  • STRIG(1)= 0 when ASCII Plus-X Terminator Laser is pointing to white pixel
  • STRIG(3)=-1 when ASCII Plus-X Terminator Laser button is pressed
  • STRIG(3)=-1 when ASCII Plus-X Terminator Laser button is not pressed

for joystic port 2 these functions are STRIG(2) and STRIG(4)

About timing

The correct distance to use the gun seems to be about 80cm between 14" monitor (tested on CM8833, older model) and head of the gun. At this distance the circle, that is visible to the transistor seems to have only about 5 pixel radius after that the light effect to result will drop locarithmically very fast. The transistor will activate pretty quickly after detecting the light. Delay is at maximum only about 2 lines (*).

When the capasitor is fully loaded it will hold the signal up about 31 lines. How well the capasitor is loaded depends of the brighness of the pixels inside the circle. This capasitor gets loaded to almost full pretty fast so I would say, that normal hit will cause signal to go on for 24-28 lines. It seems that red color is very hard for this device to detect and also other ways these timings differ depending of brightness setting, monitor type etc. How ever I would say this is example of "normal" situation.

* All lines I talk about are NTSC scanlines (with incomplete timing as normal in MSX)
PlusXelectronics.gif

Links