On Sun, Apr 4, 2021 at 3:35 PM Stephen Adolph <[email protected]> wrote:
> Hello all, > > I'm doing some TPDD software work and, of course, I like to do that on > VirtualT. > > However, getting VirtualT and real serial based TPDDs (like a real TPDD, > or LaddieAlpha running on PC, or otherwise) seems to be very unreliable. > > It isn't clear to me that serial port settings alone can solve this issue. > I've had no luck in deducing what the problem could be, and so fidding with > buffer setting, timeouts etc is just a shot in the dark. > > It gets confusing because there are clearly bugs but also multiple factors. Issues I can think of: a) Cleanly opening/closing the port at the appropriate times based on UI interaction b) Recovering from errors, closed devices c) Conflict between applications accessing the same port d) Timing dependencies in applications e) In combination with (d), Latency / data queueing / missed events or interrupts For one if you're using TS-DOS, forget it. Is this with your own client? I seem to recall writing the Linux serial port handling. It probably needs an overhaul. Maybe there's something particularly bad going on, like there's some software flow control or other cooking / smartness going on on the channel when it should just be raw bytes streams. -- John.
