Amstrad Magnum Phaser
The Magnum Phazer was released later on in the Amstrads' life, and retailed for £24.99 in the UK. It came supplied with a cassette and a disk, both containing six games.
The main reason to buy this gun was for the excellent Amstrad conversion of Operation Wolf. Playing this with a light gun on your Arnold was the arcade experience people relished but rarely got back in the 80's. The other supplied games were fun for a while, but by far the high point was Operation Wolf.
Technical
Connects to expansion port 50pin edge connector. Reportedly it uses only 4 pins: VCC, GND, LPEN, D7. Uh, that is, without decoding any address lines or /IORQ lines?
Trigger Button ---> Request via output to Port FBFEh, then check CRTC input Light Sensor ---> CRTC Light Pen Input
To read the Trigger button (to be done during vblank):
Port[BCxxh]=11h ;select CRTC register 11h old=Port[BFxxh] ;-get old value Port[FBFEh]=7Fh ;\force an edge on the lpen input Port[FBFEh]=80h ;/(depending on whether button is pressed or not) new=Port[BFxxh] ;-get new value if old=new then ... else ...
Supported Games
Mastertronic released some more games with Magnum phaser support, but they were mostly budget type Spectrum ports. (... which games???)