grr@cbmvax.UUCP (George Robbins) (12/28/87)
In article <3315@ulysses.homer.nj.att.com> eric@hector (Eric Lavitsky) writes: > Don't understand why you did this - the Micron memory board is way superior > to the Commodore design (no offense guys :-), because of the following: Eric, Eric, your board may be "better" than our board, but let's keep the advertising hype down. > 1) 4 layer PC board (CBM is two layer) - means less noise > on the bus. *I'll* guarantee you that 4 Micron boards > will work in a B2000 (won't speak for ther Germans!) It means less noise on the *board*, not necessarily less noise on the bus. It makes the boards more expensive, but might be worth it in a marginal situation. BTW, the memory boards were designed here. > 2) Socketed RAM array (CBM is soldered) - means bad chips > are easily replaced. This is a religious issue. It is generally considered that while sockets make boards easily repairable, their presence, especially in the quantity you have in a memory board, is a detriment to overall system reliability. If I have to repair a system that has chips in sockets, the very first thing I do is shove all the chips into the sockets and try again. > 3) Full diagnostics (CBM comes w/none) - means that you can > determine which chips if any are bad. A worthwhile investment. > 4) Long warranty (two years I think) Also nice. > 5) The Micron board (ASDG's design) is a superset of the > Zorro board specification. It provides full Zorro > bus buffering and arbitration on the board. Because > of this, the Micron/ASDG memory board will work in > just about any Zorro or Zorro subset box around. > The ASDG MiniRack-C was a Zorro subset box; the Micron > single slot adapater is a Zorro subset. The CBM board > expects to be plugged into a *full* Zorro backplane. A bunch of mumbly-poo that basically allows as the first ASDG expansion chassies designs were non-standard, but their memory boards were clever enough to swing both ways. This is fine and well, but implies that expansion devices designed only to support their boards, may not work with a standard board... Note that there are no defined Zorro "subsets" or "supersets", these are simply ASDG labels for what the decided to implement. We have an 86-pin expansion connector and a 100-pin expansion connector. The exact characteristics of the connectors differ in what are hopefully non-critical ways between systems. > Sorry to hear it, but there's not much you can do. If you can return the > CBM board and get a Micron board (I hear Able has it for under $350.00), > I'd recommend doing that. Not altogether bad advice. Generally, avoid mixing apples and oranges unless you understand the consequences or have some independent assurance that the combination works. One could of course keep the A2052 board and obtain an A2000 or some "Zorro standard expansion device. -- George Robbins - now working for, uucp: {uunet|ihnp4|rutgers}!cbmvax!grr but no way officially representing arpa: cbmvax!grr@uunet.uu.net Commodore, Engineering Department fone: 215-431-9255 (only by moonlite)
bryce@hoser.berkeley.edu (Bryce Nesbitt) (12/29/87)
In article <> grr@cbmvax.UUCP (George Robbins) writes: >In article <> eric@hector (Eric Lavitsky) writes: > >> ...The ASDG MiniRack-C was a Zorro subset box; the Micron >> single slot adapater is a Zorro subset. The CBM board >> expects to be plugged into a *full* Zorro backplane. | | A bunch of mumbly-poo that basically allows as the first ASDG | expansion chassies designs were non-standard... | ...Note that there are no defined Zorro "subsets" or "supersets", | these are simply ASDG labels for what the decided to implement.... Could we get some technical details on just how much of the "set" was left out? Specifically which lines have been left off of various manufacturer's delusions of "Zorro". Everyone will benifit from having this information public. Also, the "EINIT" lines on the A2000 would need to be considered a Zorro "superset", no? Facts, not fluff, please! |\ /| . Ack! (NAK, SOH, EOT) {o O} . bryce@hoser.berkeley.EDU -or- ucbvax!hoser!bryce (or try "cogsci") (") U "Your theory is crazy... but not crazy enought to be true." -Niels Bohr
daveh@cbmvax.UUCP (Dave Haynie) (01/08/88)
in article <22333@ucbvax.BERKELEY.EDU>, bryce@hoser.berkeley.edu (Bryce Nesbitt) says: > Also, the "EINIT" lines on the A2000 would need to be considered a Zorro > "superset", no? No, that's technically a requirement of the A2000 Bus, eg. Zorro II. It's also impossible to achieve externally on an A1000 or A500 without some pretty convincing magic. There's also nothing to date that uses it, at least to my knowledge. I haven't seen any of the 3rd party expansion boxes up close enough to have any comment on how close they come to full Zorro II. If such a box will work with the RAM card, Hard Disk card, and PC Bridge from C/A (just work, I don't care about driving the non-existent PC bus on most A1000 card cages), they've got to be pretty close, as these three together use most of the Zorro II features. I certainly wouldn't build such a box myself without testing all three, and anything else I can get my hands on. > Facts, not fluff, please! > |\ /| . Ack! (NAK, SOH, EOT) > {o O} . bryce@hoser.berkeley.EDU -or- ucbvax!hoser!bryce (or try "cogsci") > (") > U "Your theory is crazy... but not crazy enought to be true." -Niels Bohr -- Dave Haynie "The B2000 Guy" Commodore-Amiga "The Crew That Never Rests" {ihnp4|uunet|rutgers}!cbmvax!daveh PLINK: D-DAVE H BIX: hazy "I can't relax, 'cause I'm a Boinger!"