maddox@renoir.Berkeley.EDU (William Maddox) (06/16/86)
I recently purchased a Tall Tree Systems JRAM-AT memory expansion for my IBM AT. According to the manual, when configured in its so-called "mode 1", it functions "exactly like an ordinary IBM expansion board." I carelessly assumed that this was true; How could anyone possibly screw up something as straightforward as a memory board? Well, they did. When using this board, Xenix 1.0 nearly always panic halts with a parity error during the boot sequence. The IBM diagnostics show no problems. I contacted Mr. Troy Stone at Tall Tree technical support who informed me that they had seen this problem before, did not know what caused it, and said to tape over one of the pins on the edge connector. What he had in fact advised me to do was to disable parity error detection entirely. I insisted that this was not an acceptable solution, and that I wanted a real fix. To his credit, he offered to refund my money on the board, provided that I had purchased it directly from Tall Tree Systems. Unfortunately, I had purchased my JRAM-AT through a dealer as a special-order item. He agreed to send me a schematic when I inquired about technical details. Despite a claim that TTS was looking into the cause of the problem, when I called back a few weeks later, Mr. Stone offered only the same advice as before, and I got the distinct impression that TTS was not particularly interested in finding the cause of the problem, much less providing its customers with a hardware or software patch. I find this lack of support rather disappointing, as the JRAM-AT, if it were compatible as claimed, has much to offer the Xenix user. The situation is typical, however, of problems that I, as a Xenix user, have experienced when dealing with DOS-oriented companies, whose definition of IBM-compatible often seems to be "runs Lotus 1-2-3 and Sidekick." I would be interested in hearing from anyone who has sucessfully used a Tall Tree Systems JRAM-AT with any version of Unix(R) on an IBM-AT, or can shed some light on the cause of this problem. Bill Maddox ARPA: maddox@renoir.berkeley.edu UUCP: ucbvax!renoir!maddox BELL: 415-849-0462
farren@hoptoad.uucp (Mike Farren) (06/17/86)
maddox@renoir.Berkeley.EDU.UUCP (William Maddox) writes: [about the Tall Tree JRAM-AT expansion board] > >When using this board, Xenix 1.0 nearly always panic halts with a parity >error during the boot sequence. The IBM diagnostics show no problems. It's likely that what's happening is quite simple: the memory is not being initialized properly at boot time. All expansion memory has to be written to before it is read in order to set the parity bit correctly. I don't know Xenix 1.0, so don't know if it does this as a matter of course. I have had similar problems with expansion memory on a normal PC. I have used Tall Tree boards for quite a while, with very, very good results. I have also found them to be quite helpful when needed, and am at a loss to explain their behavior in your case. ---------------- Mike Farren hoptoad!farren
dhp@ihlpa.UUCP (Douglas H. Price) (06/17/86)
> I recently purchased a Tall Tree Systems JRAM-AT memory expansion for > my IBM AT. > > I would be interested in hearing from anyone who has sucessfully used > a Tall Tree Systems JRAM-AT with any version of Unix(R) on an IBM-AT, or > can shed some light on the cause of this problem. > > Bill Maddox I unfortunately must join the ranks of those who haven't gotten this board to work with XENIX. I have a Sperry IT, an AT clone. In my case, the machine boots up normally, but large programs which begin to use the expansion memory go non-deterministic. The board passes all of the simple memory diagnostics that I have been able to get my hands on. Now, there have been discussions in this newsgroup lately about incompatibilities of early Sperry (actually Mitsubishi) motherboards and EGAs. I wonder if this is related? -- Douglas H. Price Analysts International Corp. @ AT&T Bell Laboratories ..!ihnp4!ihlpa!dhp
root@ozdaltx.UUCP (root) (06/18/86)
In article <14389@ucbvax.BERKELEY.EDU>, maddox@renoir.Berkeley.EDU (William Maddox) writes: > I recently purchased a Tall Tree Systems JRAM-AT memory expansion for > ********** etc... ******* > I find this lack of support rather disappointing, as the JRAM-AT, if it ------- I have, in the past, worked with several clients who had Tall Tree equipment of some kind or the other. (Tape streamers, boards, etc...) All had problems, and *WE* could not get even the most remote resemblence of a straight answer from these people. This is ONE of the reasons I shy away from the *DOS based machines... there are just too many manufacturers making pereifs, seemingly for a quick buck. "Sorry sucker... we gott chur money... f*** you!" 'nuff said... Scotty ...ihnp4!cuae2!ltuxa!we53!sw013b!dj3b1!killer!ozdaltx!root DISCLAIMER: "This system is mine, so this really isn't necessary!"