Re: Plus/4 RS232 woes

From: Justin <shadow_at_darksideresearch.com>
Date: Wed, 5 Sep 2018 15:14:39 -0400
Message-Id: <5604338D-FFCD-40D0-97D2-4DF043F8ACEB@darksideresearch.com>
On Sep 5, 2018, at 10:35, Jim Brain <brain@jbrain.com> wrote:
> 
>> I can't tell what the person who designed the chip was thinking, but it's rather telling that both commodore and apple don't appear to have been aware of it when they wrote their drivers.
>> 
> Most people did not make the connection that 1.8432/16 = 115200. However, I think Commodore and Apple did understand.  At the time the devices came out, 115200 was not a bps rate in general use, and line drivers at the time would have struggled to keep up and adhere to the standard.  I also seem to recall that EIA relaxed the serial standard at some point to allow the higher speeds to comply with the signalling standard.

Apple wanted to hit 230.4kbps for their networking over RS-422, so they probably were not as cavalier as Commodore.

Justin
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Received on 2018-09-05 22:00:05

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