Richard Atkinson wrote: > > Hmm, just received this in the post. Says 'bildschirmtext' on the case - > I'm guessing that means teletext. What exactly is it, and what does it do? Don't know what teletext is. BTX=Bildschirmtext is an early German online service based on the CEPT standard, similar implementations exist at least in France and Austria, don't know about GB. You had to dial into the service with a modem or acoustic coupler at the enormous speed of 1200 baud down- and 75 baud upload speed. > Or rather, how to I get it to do what it's supposed to do? There's a lot > of ports and what looks like a pass-thru port for the power supply. There were two versions of the module, I only have version two. This has three DIN connectors on the back: 7 pin modem connector (I think this is some current loop interface), 8 pin analog RGB connector and 8 pin C64 style composite/separate video connector. The module is capable of doing at least 640x200 resolution with 4096 colours, but I think it was quite restricted to some sort of character set based graphics. Still the output is quite nice, especially in RGB mode. My module's composite output sucks, there is some sort of interference pattern. If the C64 is powered on with that module, it will display a startup message with the module version number on both the C64 and module video output. > PCB inside contains 4K of SRAM and an EPROM of unidentified size, plus a > Philips SAA video chip of some kind and some PAL colour encoding > circuitry. There's a large number of discrete devices in there too and > another 40 pin DIL IC, so perhaps it has its own processor. My version two module has an 6803 MCU with another 68xx support chip, I guess some SRAM, 32k Eprom, and a SAA video chip with another 64k DRAM. Some discrete stuff for video and modem interfacing is also there. BTW, the module was developed and manufactured by Siemens, Commodore only sold it under its name. Nicolas - This message was sent through the cbm-hackers mailing list. To unsubscribe: echo unsubscribe | mail cbm-hackers-request@dot.tcm.hut.fi.
Archive generated by hypermail 2.1.1.