8 Dec
2014
8 Dec
'14
11:54 a.m.
From: Jon Elson
Sent: Sunday, December 07, 2014 9:11 AM
Say, this brings up a question I've always
wondered about. On the
emulation microcode for the 360 series that ran decimal machine code,
such as the 1401, did they translate every address from decimal to
binary before accessing the memory, or did they just use the bare BCD
address, leaving little and big holes all over the binary address
space?
As it happens, I saw this discussed somewhere else in the last few
months by someone who actually worked on these things (probably on
alt.folklore.computers, come to think of it).
They left holes in memory while running 1401 emulation.
Rich
Rich Alderson
Vintage Computing Sr. Systems Engineer
Living Computer Museum
2245 1st Avenue S
Seattle, WA 98134
mailto:RichA at LivingComputerMuseum.org
http://www.LivingComputerMuseum.org/