barber@applga.aa.cad.slb.com (Steve Barber) (07/19/90)
Well, last night was bad news. A lightning storm was coming into the area so I shut down shade, my 3b1. Since I knew his insides hadn't been cleaned in a while, and I had a battery sitting around waiting to be installed the next time I had the time and the opportunity, I pulled him all apart, cleaned the (literally) mounds of cat fur and dust off the motherboard and power supply, and replaced the battery with a coin-type battery holder. (With battery, of course!) The humidity was high, so I wasn't too worried about static. Well, looks like I got bit anyway. On power up, I got the screen full of bit patterns, then a clear screen for a split second, then a screen of alternating all on/all off words, where it hung. (i.e.: xxxxx xxxxx xxxxx xxxxx xxxxx xxxxx xxxxx xxxxx xxxxx xxxxx xxxxx xxxxx (etc.) ) The LED pattern was: Red: ON Green: off Yellow: ON Red: off which a friend with the reference manual tells me is the code for bad motherboard memory. Now, I have 2Mb of motherboard memory, and I'm almost positive it is not socketed. I have a couple of spare 41256 RAM chips, but desoldering all those chips does not thrill me, and even then I have no idea which chip is bad. (If I *were* to go and pull all those chips, I'd most definitely stuff sockets in there...) My friend suggested that AT&T had some diagnostic EPROMs that would locate the bad chip. I seem to recall that people on the net had not been able to find these EPROMs in the past though. Then I thought I'd write and burn my own diag eproms to find the bad chip, until I realized that I had lost my assembler and linker setup for the EPROM programmer when I lost shade. So. Does anybody have any suggestions? I *have* to get this fixed, and cheaply. (I'm a student who needs a working computer next fall, but can't afford to go back to school if I spend much money getting this fixed!) Those of you with worthwhile suggestions, please send e-mail to me at: barber@applga.aa.cad.slb.com. I'll try to monitor these groups from work, but I might miss something, so e-mail is best. Thanks a million, Steve -- Steve Barber, Schlumberger CAD/CAM, Ann Arbor, Michigan Work: barber@applga.aa.cad.slb.com (313) 995-6000 Home: steveb@shade.ann-arbor.mi.us (313) 665-0884