schuh@geowhiz.UUCP (David Schuh) (07/03/85)
Has anyone ever had this message pop up on your screen in about 20 point high letters. After which you must hard reboot? dit dit dit dahhh: PARITY CHECK 1 What does this mysterious message mean, these crashes seem to happen randomly, but I'm sure there related to something we can fix. The grubby details: 1) PC with Enhanced color, 8087, 256Kb. 2) Kinetic Systems Camac interface card (2925) 3) 50 wire cable to the camac crate controler (also Kinetic) We are trying to narrow this thing down, it could possably be the 2925 card, but it seems unlikely as in operation it works beautifully. However when I run the diagnostics provided with the pc, and enter 0 for run diagnostics, the disk just spins and spins, but if I take the card out, Hunky Dory, any ideas? I thougth that the location was bad and we were getting rf interference, but that does not seem to be it. Could glitches comming through the cable cause this kind of crash? I realize that this probably isnt enough to go on to really solve the question, but I would even be gratefull for a partial list of things that cause that parity check message. I can not find it anywhere in my documentation (I dont have the Tech Ref manual yet). Please respond by mail. uwvax!geowhiz!schuh thanks in advance dave Working for High Energy Physics, UW Madison. uwvax!geowhiz!schuh
jamesa@dadla.UUCP (James Akiyama) (07/07/85)
> Has anyone ever had this message pop up on your screen in about > 20 point high letters. After which you must hard reboot? > > dit dit dit dahhh: > > PARITY CHECK 1 > > What does this mysterious message mean, these crashes seem to happen > randomly, but I'm sure there related to something we can fix. > The grubby details: > > 1) PC with Enhanced color, 8087, 256Kb. > 2) Kinetic Systems Camac interface card (2925) > 3) 50 wire cable to the camac crate controler (also Kinetic) > > We are trying to narrow this thing down, it could possably be the > 2925 card, but it seems unlikely as in operation it works beautifully. > However when I run the diagnostics provided with the pc, and enter > 0 for run diagnostics, the disk just spins and spins, but if I take the > card out, Hunky Dory, any ideas? > > I thougth that the location was bad and we were getting rf interference, > but that does not seem to be it. Could glitches comming through the > cable cause this kind of crash? > > I realize that this probably isnt enough to go on to really solve the > question, but I would even be gratefull for a partial list of things > that cause that parity check message. I can not find it anywhere in my > documentation (I dont have the Tech Ref manual yet). > > Please respond by mail. > uwvax!geowhiz!schuh > > thanks in advance > dave > Working for High Energy Physics, UW Madison. > uwvax!geowhiz!schuh Normally, parity check messages from an IBM PC should be of the form: PARITY CHECK X YYYYY where X is: 1 if the error occurred in system board memory 2 if the error occurred in expansion board memory and YYYYY indicates the bank of failing memory. This is determined by scanning to see if a failing address can be identified. If it can be identified, the address appears as a five-number code. If the failing address couldn't be identified, five question marks should have been displayed.
shanks@teneron.UUCP (Dave Shanks) (07/09/85)
In article <205@geowhiz.UUCP> schuh@geowhiz.UUCP (David Schuh) writes: >Has anyone ever had this message pop up on your screen in about >20 point high letters. After which you must hard reboot? > > > PARITY CHECK 1 <Details of the problem follow at the end of this article> I too have seen this problem recently when running a particular program. The program runs in one of the graphics modes and at the time of the parity check is writing characters out to the screen. The screen clears and the message "PARITY CHECK 1" appears at the upper left corner of the screen. The message is in characters appropriate for a 40x25 screen. No string follows the message to tell me where to look for a bad memory chip. My suspicion is that this program (which I copied off an RBBS) is doing something to cause the system to generate this message. Perhaps it is running through some interrupt vector which causes this message. The message always appears at the same place in the program. I do not believe that my memory chips are failing since neither the power on self test nor the advanced diagnostics can detect any problem with the computer's memory. My computer's configuration follows: IBM PC/XT (256K RAM on motherboard) Quadram Quadcolor board (an IBM Color Graphics Adapter look alike) AST Six Pack Plus (384K RAM, serial, parallel, clock, joystick) IBM Asynchronous Communications Adapter Any ideas as to how this message could be generated *without* an actual memory failure? Is it possible for software to cause a parity error (deliberately or accidently) without a hardware failure? Any suggestions will be appreciated. >What does this mysterious message mean, these crashes seem to happen >randomly, but I'm sure there related to something we can fix. >The grubby details: > > 1) PC with Enhanced color, 8087, 256Kb. > 2) Kinetic Systems Camac interface card (2925) > 3) 50 wire cable to the camac crate controler (also Kinetic) > >We are trying to narrow this thing down, it could possably be the >2925 card, but it seems unlikely as in operation it works beautifully. >However when I run the diagnostics provided with the pc, and enter >0 for run diagnostics, the disk just spins and spins, but if I take the >card out, Hunky Dory, any ideas? > >I thougth that the location was bad and we were getting rf interference, >but that does not seem to be it. Could glitches comming through the >cable cause this kind of crash? > -- Dave Shanks ..!tektronix!reed!teneron!shanks Teneron Corp. 6700 SW 105th Suite 200 Beaverton, OR 97005 (503) 646-1599
lindley@ut-ngp.UTEXAS (John L. Templer) (07/14/85)
> >Has anyone ever had this message pop up on your screen in about > >20 point high letters. After which you must hard reboot? > > > > PARITY CHECK 1 > My suspicion is that this program (which I copied off an RBBS) is doing > something to cause the system to generate this message. Perhaps it is > running through some interrupt vector which causes this message. The > message always appears at the same place in the program. I do not > believe that my memory chips are failing since neither the power on > self test nor the advanced diagnostics can detect any problem with the > computer's memory. I think I have an idea what might cause this, at least I found one thing that does cause it. I was playing around with the timer chip, trying to discover how to program it to drive the speaker, working from the Technical Refference Manual. What I did was use the sequence that the BIOS uses to make the error beep during the start up diagnostics, but changing some of the parameters. (No, I don't remember which I/O ports correspond to the timer chip.) In addition to the many varied error messages and lockups I got as a result, one time the "PARITY ERROR 1" message appeared on the screen, and the soft reboot didn't work. I would have thought that the timer chip wasn't so essential to the opperation of the pc. I though the 8088 used it's own internal clock. Oh well, maybe someone out there can tell me how to get the timer chip to work the speaker. -- ~~ John L. Templer, University of Texas at Austin ~~ {allegra,gatech,seismo!ut-sally,vortex}!ut-ngp!lindley "Oh, I liked it well enough-- only it was so dusty and hot, and the elephants did tease so!" (Can you recognise the character speaking?)
bob@nbires.UUCP (Bob Bruck) (07/17/85)
> ...I was playing around with the timer chip, > trying to discover how to program it to drive the speaker, working from > the Technical Refference Manual. > > What I did was use the sequence that the BIOS uses to make the error > beep during the start up diagnostics, but changing some of the > parameters. (No, I don't remember which I/O ports correspond to the > timer chip.) In addition to the many varied error messages and lockups > I got as a result, one time the "PARITY ERROR 1" message appeared on > the screen, and the soft reboot didn't work. > > I would have thought that the timer chip wasn't so essential to the > opperation of the pc. I though the 8088 used it's own internal clock. > Oh well, maybe someone out there can tell me how to get the timer chip > to work the speaker. > -- > The 8253 contains 3 clock channels. Channel 0 is used for the software driven time-of-day clock, channel 1 is used for memory refresh, and channel 2 is used to support the tone generation for the audio speaker, producing a square wave at 1.19318 MHz. See the IBM PC technical reference for more details. Given this, you probably accidentally re-programmed channel 1, disabling memory refresh and thus causing the parity error you described. Bob Bruck (hao | allegra | ...)!nbires!bob
dmt@mtgzz.UUCP (d.m.tutelman) (07/17/85)
> I was playing around with the timer chip, > trying to discover how to program it to drive the speaker, working from > the Technical Refference Manual. > ..... In addition to the many varied error messages and lockups > I got as a result, one time the "PARITY ERROR 1" message appeared on > the screen, and the soft reboot didn't work. > > I would have thought that the timer chip wasn't so essential to the > opperation of the pc. I though the 8088 used it's own internal clock. I believe that one of the channels on the timer chip is used to generate the refresh signal for the dynamic RAM. If that got stretched out significantly (or turned off altogether) it would guarantee some sort of memory fault. Maybe that's what happened. Dave Tutelman Physical - AT&T Information Systems Holmdel, NJ 07733 Logical - ...ihnp4!mtuxo!mtgzz!dmt Audible - (201)-834-2895