EMC 64K chip memory

[kimery at wdl1.UUCP]

/ wdl1:net.unix-wizards / news at seismo.CSS.GOV (UseNet News) /  1:10 pm  Jul 23, 1986 /
}.....
}The installation of seismo took about SIX hours. Two to install the
}memory and FOUR hours of me and the CE arguing over whether Unix
}was broken since it only found 8 of the 16 M bytes. He claimed his
}diagnostics found the full 16Mbytes. Unix only found 8.

The EMC 4 Meg memory boards have two modes to them.  One is an interleaved
mode and the other is non-interleaved  (god isn't that amazing, how does
he do it??).  If you look at the 2 page Xerox documentation that comes
with the stuff (I don't care who installs it, I always read the docs...)
you will notice that the is a line that says to run diags do the following:
		DEP (something)
		EX  (address) 
	Then run the EMC diag, or the DEC diag3.

(THIS IS THE IMPORTANT PART)
	The docs also say to do another DEP to turn the memory back into
interleaved mode.  This does not happen automagically.

Yes, if you do forget it only shows up as 8M instead of 16M.  Yes, I
forgot to do that in all the exitement, and it took me a few minutes
to figure out what I had done wrong....

		Sam Kimery
		kimery at ford-wdl1
		decvax!sun!wdl1!kimery