gak@gakbox.Sun.COM (Richard Stueven) (01/13/90)
Folks, One of my expansion boards went south the other morning. I found where the problem is, and I think there's probably a cheap way to fix it, except I'm not quite sure how to go about it. Here's the detail: I got a kernel panic that looked like this: *hpte: 0x6201 type = 0x1F, pid = 9, pc = 02DFA, rps = 0x2000, p = 0x45C9C GSR = DD00, BSR0 = FE04, BSR1 = B017, PHYSPF = 201 D0 = 66, D1 = C, D2 = 1C, D3 = 2FFFF7 D4 = 2FFFD8, D5 = 0, D6 = DD00, D7 = 2FFFF7 A0 = 2FFFF6, A1 = 400000, A2 = 4B018, A3 = 70A54 A4 = 708B6, A5 = 3000, A6 = 70852, A7 = 2FFEE0 #NMI (parity error) at 0x82076 (*hpte: 0x4201) panic: NMI (kernel parity error) So I booted the Diagnostics Floppy and ran the memory tests. Here's what I got: Test: Expansion memory test Subtest: Data bus test (walking 1's) Pass: 7 Error: Memory error at Address 6: Wrote 1, Read Back 5. When I told it to continue, rather than aborting, every address that ended with either a 6 (binary 0110) or an E (binary 1110) failed with the same message. I made the problem go away by removing the expansion memory from slot 1 and moving the expansion memory from slot 2 to slot 1. The machine is fine (not even any filesystem damage!), but I'd like to get that extra 0.5M back. Now my hardware expertise is limited to knowing which end of the power cord goes into the wall, but it seems to me that the problem can be traced to just one single memory chip, or maybe one row or column. But which one? Any ideas, or am I off base here? On a related note, where are all those hex numbers documented (the ones that appear in a panic message)? Which ones are significant as far as diagnosing problems? The only FM that I haven't R'd is the Hardware Reference (thx Lenny)...pointers are greatly appreciated. P.S. One possible cause of the memory problem could be that the current coming out of my walls fluctuates in the range 120-130VAC! I have one of those power strip/surge protectors, but I'm skeptical as to its efficacy. Does anybody sell Cheap UPS units suitable for home use? thx gak Richard Stueven gak@sun.com I like to know what I'm doing when I'm doing what I do when I'm doing it because I don't know what to do when I'm not doing it. - S.Ridgeway