Changes

Dk'tronics Lightpen

377 bytes added, 13:26, 12 January 2010
/* Technical */
== Technical ==
Uses I/O ports: [[I/O_Port_Summary|#1C00]] and [[I/O_Port_Summary|#1F00]](as shown in above BASIC example) * #1C00 and #1F00 are bad decodings /mirrors of port [[CRTC]] ports #BC00 and #BF00 the ports used by the CRTC.* These ports will clash with other hardware.(but do work more or less)* A15=0 doesnt't trigger the [[Gate Array]] (which would also require A14=1)* A13=0 does trigger [[Upper ROM Bank Number]] (but the IN's don't cause problems since the ROM bank is write-only, the OUT's do activate bank 16 and 17, but usually don't cause problems since these banks usually contain mirrors of the BASIC ROM)
The Lightpen uses the CRTC /LPEN input on the expansion port.
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