Hi Alex,"Alex Freed" <alex_news@mirrow.com> wrote in message news:hffp9t$2gg9$1@adenine.netfront.net...
RedskullDC wrote:Don't suppose you (or anybody else?) would have a copy of the Videx manual,and would be able to do a decent scan of the schematic page? Only online copies I can find are too lo-res to make out the schematic. Considerably more difficult to emulate without it....I do have a relatively low-res but readable schematics. It's rather straightforward using the 6845 controller and static RAM. What I don't have is the ROM. If anyone disassembles it it may so happen that the 6845 only needs to work in one mode and not all the registers are needed.-Alex.
Roms are no probs: http://mirrors.apple2.org.za/Apple%20II%20Documentation%20Project/Interface%20Cards/80%20Column%20Cards/Videx%20Videoterm/ROM%20Images/ I haven't had a "real" Videx card since about 1983, though from memory it only uses stock 80x24 modes. There were a few hacks for slightly larger width/height combos, though you can't go too far before the screen wraps due to the hardware scrolling/limited memory. Slightly off topic: Tandy Model 3/4 used a modified version of the 6845 which only allowed 2 modes of operation (80x24, 64x16). Most of the registers were not read/writeable. Cheers, Leslie