29 Nov
2010
29 Nov
'10
9:02 p.m.
From: Ian King
Sent: Monday, November 29, 2010 12:22 PM
Another DEC machine to use an embedded computer as a
console is the KL-
10 processor. It uses an 11/40 running a modified version of RSX-11
called RSX-20F. Given that the KL was introduced in 1975, it predates
the 11/780 in using this approach. -- Ian
Specifically, RSX-20F is a variant of RSX-11M v3.2 (at least, that's the
documentation you got when you bought the -20F source license), with some
features brought in from RSX-11D (though what came from -11D is never made
clear in the documentation). It runs without memory management in 28KW
(56KB) of core.
-20F tasks are restricted to three partitions: the resident EXEC; GEN(eral),
for utilities; and F11TPD (Files-11), which is also used for non-resident
EXEC routines.
The disk driver has been modified to use the Tops-10/TOPS-20 18-bit sector
size, with 16 bits right-justified and the two top bits set to 0.
Rich Alderson
Vintage Computing Sr. Server Engineer
Vulcan, Inc.
505 5th Avenue S, Suite 900
Seattle, WA 98104
mailto:RichA at vulcan.com
mailto:RichA at LivingComputerMuseum.org
http://www.PDPplanet.org/
http://www.LivingComputerMuseum.org/