From: John Wallace [johnwallace4@yahoo.dotco.dotuk] Sent: Tuesday, April 15, 2003 7:36 AM To: Info-VAX@Mvb.Saic.Com Subject: Re: Alpha emulator - 21172 vs. 21174 logic core chipset "Timothy Stark" wrote in message news:ufKcnSXzm8eLgQujXTWcqA@speakeasy.net... > "Dave Weatherall" wrote in message > news:DTiotGxQ0bj6-pn2-KIvQbsTlW7So@localhost... > > Best of luck with the project Tim. Just had an evil thought. An Alpha > > emulator running in a 64-bit Opteron running VMS faster than on > > Itanium, which is where the evil comes in :-) > > Hmmm. But my Alpha emulator is running slowly. :-) I implemented many > emulated instructions on it and ran SRM console successfully. According to > my debug log file, SRM console moved itself to loc 40.0000 from anywhere and > decompressed itself (like compressed Linux kernel) then finally jumped into > loc C000... It took a few seconds to complete decompression. I now am > working on logic core emulation for accessing I/O devices right now. > > Well I have more two questons for you here. I read my AlphaPC 164LX > technical manual and noticed that core logic chipset is 21174 but I have > 21171 and 21172 tech docs. I was looking for 21174 docs but can't find it. > What are difference between 21174 and 21172 core logics? I noticed that not > much difference between their space address maps. > > Thank you! > Tim Stark > > Still looking? Given a bit of historical knowledge of these things as a starter, here's what I found... Iirc, the 21172 chipset was developed by Digital Semiconductor folks as the system/memory interface chipset for 21164. The 21174 was a low-cost single chip alternative developed for (by?) the PWS folks and also used on PC164LX etc. 21174 was often referred to as Pyxis (Google finds lots of Linux/Alpha references to Pyxis). The manuals below should tell you a lot more. Googling for "21172 21174 alpha" and ignoring the initial junk led me to http://www.cse.unsw.edu.au/~danielp/cs1/l4alpha/alpha_docs.html where there seems to be an interesting collection of Alpha docs, including 21172 and 21174 Core Logic Chipset technical manuals. I haven't looked at them (limited net access now). Also available at that site, the Alpha Architecture Handbook. Google also finds http://www.0xfi.com/oslib/topx.html where there's another fine collection of "weird stuff", not all correct (e.g. 21164 and 21164 PC aren't the same chip). But it does have a copy of a Digital Technical Journal article titled "The Design of the 21174 Memory Controller for DIGITAL Personal Workstations", and various other bits on Alpha and other architectures. Corrections and clarifications always welcome. good luck john