On Tue, Sep 06, 2016, Cameron Kaiser wrote: > > Interesting. I've been trying to get a WiFi device for the Commodore > > 8-bits working consistently in 9600 bps mode, and have just been > > assuming the garbage characters I get when I receive a screenful of text > > all at once were due to buffer overruns. The garbage characters there > > look like actual garbage, not like partial CSIs like [3;1m or whatever. > > Unless you're using an ACIA cartridge, 9600bps on the C128 is problematic, > and impossible on the C64.
Not quite; someone named Daniel Dallmann found a way to do it on the user port, on both 64 and 128 (in the 1990s, I think). It's commonly called "UP9600". I've only found one terminal program* so far that actually performs well and doesn't drop characters or bring up garbage ones, on the device I mentioned (I have never tried it with a proper modem). I'm not sure what's different about the CIAs in the 64 and 128 but, in the case of this specific hack, it's theoretically easier to deal with a 64 -- or at least a 128 with no 1571 or 1581 -- because the 9600bps hack clobbers the SRQ line that those drives use for fast serial operations. (Things still work if you turn them to slow mode, as happens when you boot directly into 64 mode.) But I find that I never get it to work non-problematically except when I use that one terminal emulator using the C128's VDC for display. I'm not sure how much the 40-column mode's 1MHz clock contributes, and how much VIC emulated 80-column mode and the VIC's scrolling speed, contribute to the problem. (Will have to try it with true 40-column mode, but then the actual viewport will fill with characters and need a scroll twice as fast.) * The terminal emulator I've had success with is NovaTerm 9.6. > > If you *are* using an ACIA cartridge, then 9600bps is well within spec and > should "just work." I'd look at your driver instead. A buffer overrun > should just drop characters, not munge them. I wish I could get more than one-sentence responses from the developer of the device. Hopefully he'll fix it in the future, if I can make a good case for it. > > -- > ------------------------------------ personal: http://www.cameronkaiser.com/ > -- > Cameron Kaiser * Floodgap Systems * www.floodgap.com * ckai...@floodgap.com > -- Burglar alarms: For the man who has everything! > ---------------------------- -- Eric Christopherson
