From: utzoo!decvax!harpo!floyd!cmcl2!philabs!sdcsvax!sdccsu3!sdcvax!bmcg!rasp Newsgroups: net.micro.atari Title: Re: CRASH! Article-I.D.: bmcg.209 Posted: Wed Feb 9 18:41:35 1983 Received: Sat Feb 12 06:57:08 1983 References: utzoo.2788 uwvax.743 Here is some accumulated lore about crashes and glitches on the ATARI: 1. When you clean the contacts, clean all of the contacts! This includes CAREFULLY removing the ROMs from their sockets, GENTLY erasing oxidation from the pins, and reseating them. 2. When you use an eraser to clean off the contacts, be VERY gentle. The precious-metal coating is extremely thin; and, when that gets rubbed off you're in for a lot of oxidation problems. 3. As a rule of thumb, with gold-to-gold conections, the problem won't be oxidation... just accumulated dirt. The clean-up period for this should be on the order of months. For gold to silver there is a mild oxidation problem that could require clean-up on a one or two month basis. If it is gold-or-silver to something else, like German silver or solder, the service interval may be days or weeks depending upon ambient temperature and atmospheric contaminants; e.g., if you live near a paper mill or a rubber plant with the resulting corrosive atmosphere you have got a real problem. 4. One other bit of unpleasantness is that some alternate sources for add-in memories had a problem EXECUTING code out of high memory. It turns out that the 6502 makes adjacent accesses to memory when fetching code while it makes less frequent access to memory on data fetches. This means that a memory test that only accesses data in memory won't detect the problem. What is needed is a test that moves a piece of relocatable code through the area under test and executes it. The only problem there is that it won't pick up pattern sensitivities. Oh well! The nice part about it is that the manufacturers own up to the problem when asked, and their warranties are still in effect. 5. Still another little mystery is the misbehavior of the system if you fool around with the joystick at inopportune times; e.g. during disk accesses, etc. I'm not entirely pleased with the explanation; but, it could be an electro- magnetic interference problem. Solutions are to avoid keeping your computer in a room with nylon carpets (static build-up) or any other insulating material. Of course, as far as diddling with the joystick while accessing the disk goes, it's simply a case of: "Doctor, it hurts when I do this." ... " So, don't do this!" Good luck with your machines. Ron Perloff Burroughs Micro Components Group PO Box 28810 San Diego, CA 92127 (619) 451-4519