I'm forwarding a message that Jeff Rulifson sent to our internal
project mailing list so that the rest of you can read it. (01)
We're starting to suffer from silo clash with these cross posts to
various closed mailing lists. I'd like to propose that we move this
discussion to hyperscope-dev@blueoxen.net, as this discussion is
relevant to all of us and I'd like it to be publically archived.
Instructions for subscribing are at: (02)
http://blueoxen.net/c/hyperscope/wiki.pl?MailingLists#nid7 (03)
On a related note, is there a public site for the Augment NLS
Restoration Project? We're going to be scavenging / creating a lot of
technical notes on Augment, and I'd also like those to be publically
available as well. (04)
-Eugene (05)
----- Forwarded message from Jeff Rulifson <jeff@rulifson.name> ----- (06)
Date: Sun, 12 Feb 2006 20:58:22 -0800 (PST)
From: "Jeff Rulifson" <jeff@rulifson.name>
To: <bootstrap-nsf@ws.blueoxen.net>
Subject: [bootstrap-nsf] Re: chord keyset
Reply-To: bootstrap-nsf@ws.blueoxen.net (07)
Everyone: Some history -- As I remember the SDS940 implementation, the OS
concatenated the three mouse bits with the 5 chord keyset bits to make an 8
bit character. The keyset was the low order 5 bits and the mouse was the top
3 bits. This produced 255 characters. (08)
These characters were remapped to match the octal ASCII characters from the
keyboard. I.e., when used with the left hand a single stroke with the left
thumb produced a 001 which was remapped into a 061 to match the "a" from the
keyboard. I remember this because, when reading a core dump, we could all
decode octal strings by putting down our left fingers and feeling the
character. 123? Hmmm, left ring finger, index finger, and thumb. That's an
"s". Given that one understood how upper and lower case were mapped. (09)
The mouse buttons could be used 1, 2, or even 3 at a time to produce the top
3 bits and give the full 255 character ASCII character set. (010)
The character stream from the mouse/keyset was merged with the character
stream from the keyboard. The high level user interface code did not
distinguish between keyboard input and mouse/keyset input. (011)
I'm reporting this because I began to wonder how mice work today. Can they
report simultaneous clicks? To get the same effect as the 940, will the
mouse driver also need to be redone? Will that even help? Are they hardware
limited and can only report one button at a time? (012)
Maybe there is a better way that will fit with available equipment? (013)
Jeff (014)
--
======================================================================
Eugene Eric Kim ......................... http://public.xdi.org/=eekim
Blue Oxen Associates ........................ http://www.blueoxen.com/
====================================================================== (015)
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