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Re: KA48 System Board Specification (Re: KA48 / VAXstation VLC cache question)



On Mon, 24 Aug 2015, Felix Deichmann wrote:

Nevertheless, can anyone think of a procedure to determine the real
cache size programmatically and reliably? Would be fun to compare
different machines, also VLC and KA660.

I think it should be easy. The ENABLE_BANK bits in BEHR register description shows how to detect if a bank has been disabled, so it looks like it should just be a matter of counting how many banks are enabled.
Now that I have my VLC systems set up, I can test that.

Also, after I started comparing the specification document and comparing values against the current cache enable code, it looks like it's actually close to correct. It looks like the only thing missing is clearing all the valid flags in the cache, and I'm wondering if the ROM is my VLC systems might be doing that before booting.

I ran the 5.1 package version of dhrystone and got much better results that John was seeing.

Mike

---
Michael L. Hitch                        mhitch%montana.edu@localhost
Operations Consulting,  Information Technology Center
Montana State University, Bozeman, MT     USA


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