Subject: Re: Character-doubling problem with 3MAXPLUS SCC interface
To: Phil Tait <Philip.Tait@phxase.allied.com>
From: Simon Burge <simonb@telstra.com.au>
List: port-pmax
Date: 09/23/1997 11:55:52
On Mon, 22 Sep 1997 17:20:34 -0700 Phil Tait wrote:
> 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.
You didn't say what version of NetBSD you're using. This problem was
fixed since the release of NetBSD 1.2. If you're running a fairly
current kernel, you shouldn't be seeing this. The relevent bit to look
at in scc.c is a few "DELAY(2)"s. Let me know if you need more info on
this.
Simon.