Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!watmath!clyde!burl!ulysses!mhuxl!ihnp4!zehntel!hplabs!sri-unix!prindle@NADC.ARPA From: prindle@NADC.ARPA Newsgroups: net.micro Subject: Re: music application for the c64 Message-ID: <12553@sri-arpa.UUCP> Date: Fri, 17-Aug-84 08:26:58 EDT Article-I.D.: sri-arpa.12553 Posted: Fri Aug 17 08:26:58 1984 Date-Received: Mon, 20-Aug-84 01:22:01 EDT Lines: 16 Apparently, much of the traffic on net.micro.cbm never makes it to the ARPANET, because I never saw the original article. But anyway, the C64 joystick trigger button doesn't interrupt the cpu (it does toggle a line on the VIC chip which causes the VIC chip to save the light pen raster coordinates). Furthermore, the joystick ports are only 5 bits each and are shared with the keyboard scan ports (contol port 1 is 5 rows of keyboard in, control port 2 is 5 columns of keyboard out scan), so the keyboard scan would have to be disabled in the kernel before you could assume complete control over these ports. I don't know what kind of D to A conversion was required, but 5 bits only gives 32 possible analog levels. Does anyone know why ARPANET coverage of net.micro.cbm seems so sporadic? Frank Prindle Prindle@NADC.ARPA