9 Sep
2016
9 Sep
'16
4:11 p.m.
If your CPU is an 11/73 (which can directly
'access' [hate that verbism
:-] all of memory from ODT, unlike the 11/23 which is restricted to the
bottom 256KB), try playing around with a failing location, and its
alternative, directly, and see if a store of random data into one can be
read back directly from the other
Note: The 11/'73' CPU powers up with the cache enabled, even for ODT!
So if you write xxx into some location, if you then read it back, you will get
the correct data even if the memory location is busted - the CPU is getting
the (correct) data from the cache. To have your 'memory' reads and writes
actually go to the memory, you need to turn off the cache:
17777746/ 02000
Note that starting the machine does an INIT, which will again enable the
cache.
I'll start the Computer History wiki page for this
board with that info.
Started:
http://gunkies.org/w/index.php?title=CMV-4000
Currently has only the memory chip info, I'll add the config stuff as I get it
doped out.
Noel