I see that "jonathon" fixed the character-doubling on OUTPUT problem by
adding DELAY(2) after SCC_WRITE DATA() back in 1995 (see excerpt from
source-changes at end of note).

I'm seeing a character-doubling problem on INPUT (reading an instrument
at 1200baud).  I'm looking for informed opinions as to whether it's
appropriate to assume symmetry, and add DELAY(2) after SCC_READ_DATA();
or maybe someone has a better idea for a fix.

----------------------------------------------------------
jonathan
Mon Sep 25 00:30:47 EDT 1995
Update of /a/cvsroot/src/sys/arch/pmax/tc
In directory pain.lcs.mit.edu:/b/tmp/cvs-serv26186

Modified Files:
        scc.c
Log Message:
Force a delay after calling SCC_WRITE_DATA() to give the chip
registers time to settle. DELAY(2) is reportedly enough.  Without the
delay, output characters are occasionally doubled.
----------------------------------------------------------

--

Philip J. Tait.....AlliedSignal Engines, Phoenix, Az.....+1.602.231.7104
PJTait@iee.org