tty input and output at different speeds?

Perry Scott perry at hpfcdc.HP.COM
Fri Oct 3 01:32:52 AEST 1986


>The machine can output genuine 19200,
>but loses characters when processing input on a tty line at
>faster than 1200. This means that function keys on a VT-100
>compatible (which transmit a multi-char sequence beginning
>with ESC) sometimes aren't properly received.

This sounds like you aren't using a buffered interface.  This kind
of problem occurs when the CPU can't service the interrupt in time.
The best solution is to buy a buffered interface - it's probably
cheaper than spending time to make the stty/driver hacks.

>Obviously I'd have to hack stty(1) and getty to grok split speeds.
>Are there any other gotchas I should be aware of?

Yes.  Your hardware has to grok the split speeds too, as well as the
driver.

Perry Scott
..{ihnp4,hplabs}!hpfcla!perry-s



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