This article was posted to the Usenet group alt.hackers in
1995; any technical information is probably outdated.
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Re: Another first post.
Article: 7474 of alt.hackers From: btomlin@crl.com (Bruce Tomlin) Newsgroups: alt.hackers Subject: Re: Another first post. Date: 3 Mar 1995 10:44:24 -0800 Organization: San Antonio, TX Lines: 17 Approved: nobody Message-ID: 3j7o28$lfe@crl12.crl.com Reply-To: btomlin@aol.com NNTP-Posting-Host: crl12.crl.com X-Newsreader: TIN [version 1.2 PL2] Status: RO
someone@somewhere.org wrote in alt.hackers: >The old Color Computers (Coco's) could not display lower case, instead it >used inverse video to symbolize lower case characters. A new revision of >the Coco's had a Video Display Generator that could support lowercase, but ObMyHack: I did a software solution. I went into graphics mode and painted the characters on the screen, plus I got black text on a white background (sort of... NTSC artifacting gave blue and red edges to vertical lines). The only hard part was scrolling, in which I learned my first lesson about fast memory moves on Motorola processors. I used the PSHU/PULU (or maybe PSHS/PULS) instructions to use all the registers I could to move as much data as possible in one instruction. I think I even wrote an OS/9 driver to do this. The downside is that screen memory took up 6k, and this was long before the CoCo3.
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