pcoderdude14 Posted January 14, 2018 Author Share Posted January 14, 2018 If you get to the point where you need some new EPROM DSR chips, FYI I have both originals and MG upgrades.I also have a mod that removes DSK4 permanently (if you have a RAMdisk designated as such). I would be interested on getting a "set" of these chips from you. Could you please contact me , thru email, at >jstimatz2015@yahoo.com< to discuss this more ... Thanks... Jt Quote Link to comment Share on other sites More sharing options...
marc.hull Posted January 14, 2018 Share Posted January 14, 2018 The possibilities with the highest likelyhood are. 1) 9901 has issues. It can be replaced easily and might clear things up. 2) your PALs are cooked which means your card is bricked until someone goes sherlock on a good one so they can be replicated. All of the card decode is done in the PALs. It sounds like your address line decode has gone haywire. Good luck. 1 Quote Link to comment Share on other sites More sharing options...
RickyDean Posted January 15, 2018 Share Posted January 15, 2018 The possibilities with the highest likelyhood are. 1) 9901 has issues. It can be replaced easily and might clear things up. 2) your PALs are cooked which means your card is bricked until someone goes sherlock on a good one so they can be replicated. All of the card decode is done in the PALs. It sounds like your address line decode has gone haywire. Good luck. He might be able to exchange the pal from his bad card to temporarily see if they work on the good card. That will let him know if they are bad. I would, as I expect to find on mine that it is a bad solder connection or trace. At least mine now goes to the title screen. Quote Link to comment Share on other sites More sharing options...
marc.hull Posted January 15, 2018 Share Posted January 15, 2018 Well I hope you are right. I really don't know if all Corcomp FDC PAL equations are equal. The 12L6nc has dedicated in/out pins ( if I am remembering right) so no possibility of damage ( check the data sheet first) in swapping. I just know that both those IC's are connected straight to the PEB without buffering and that is the source of my doubt. As a general question. Does anyone here have the capacity ( or is it possible) to read out the PAL state with or without security ? This has been an on going issue for quite a while and a replacememt would be very benificial. Quote Link to comment Share on other sites More sharing options...
+arcadeshopper Posted January 16, 2018 Share Posted January 16, 2018 I would be interested on getting a "set" of these chips from you. Could you please contact me , thru email, at >jstimatz2015@yahoo.com< to discuss this more ... Thanks... Jt you already did.. i resell his chips, he mailed them to you Greg Quote Link to comment Share on other sites More sharing options...
pcoderdude14 Posted January 18, 2018 Author Share Posted January 18, 2018 Hey All! :-) you already did.. i resell his chips, he mailed them to you Greg Ok. I thought so, when I saw his email addy... Thanks Greg ! Jt Quote Link to comment Share on other sites More sharing options...
Ed in SoDak Posted April 1, 2018 Share Posted April 1, 2018 (edited) Interesting read! Stuart directed me here from my thread about my dead-in-the-water TI php1850 sidecar disk controller. Any updates on fixing the CorComp cards? I'm guessing the TI won't have any PAL chips. <pray> -Ed Edited April 1, 2018 by Ed in SoDak Quote Link to comment Share on other sites More sharing options...
+Ksarul Posted April 1, 2018 Share Posted April 1, 2018 There are PALs in the 1850, but TI's internal documentation usually included the equations for their PALs, so it would be possible to recreate them. You'd have to look into the 1980 version of the disk controller hardware specs to get the right PAL equations, as the 1982/1983 versions of the same document only included the equations for the PEB card. I just spent a while hunting on WHT, and most of the hardware specs don't seem to be up there anymore. I'll have to go digging in my scans to see if I still have them. . . Quote Link to comment Share on other sites More sharing options...
+Schmitzi Posted April 1, 2018 Share Posted April 1, 2018 Is that two switches on the back of the 1985 Revision above the edge card connector for the external drive(s)? I never saw that card before. .... Although, the one with the two push-button switches has got me intrigued, never seen a CC-FDC with that arrangement. Any more info on that guy?? ... Will be back... -Dano Hi, where do you see this card with the 2 push buttons on the back side here ? Can you please point me there ? My only hint is that it has to do with Miller Graphics (maybe), and that the 2 push buttons are for: UPPER BUTTON: <Pressed> -> CRU=1000 / <Released> -> CRU=1400 LOWER BUTTON: <Pressed> -> "Lower Block" / <Released> -> "Upper Block" (I don´t know what that with the "Blocks" means"... memory ?) I saw that on a pic from a german card, some time ago. xXx Quote Link to comment Share on other sites More sharing options...
fabrice montupet Posted April 1, 2018 Share Posted April 1, 2018 (edited) I had problems with this Corcomp FDC too. One of them stopped working after the power supply of a PEB died. Result: The two PAL chips passed. I have replaced them and all is OK now.The problem of this card is its poor design. It doesn't have buffers to protect the PALs. It's a shame because it is easier to change 74LS244/245 than changing PAL chips hard to find or neccessiting material to program new ones. Edited April 1, 2018 by fabrice montupet Quote Link to comment Share on other sites More sharing options...
+Ksarul Posted April 1, 2018 Share Posted April 1, 2018 Fabrice, do you have the JEDEC files for the CorComp Disk Controller PALs? We've been trying to find unlocked copies of those for quite some time. . .for that matter, usable JEDEC files for any card's PAL sets would be useful things to place in one of the community repositories. Quote Link to comment Share on other sites More sharing options...
fabrice montupet Posted April 1, 2018 Share Posted April 1, 2018 (edited) Alas, I can't help you The card died six or seven years ago. As I had no 12L6 programmer and no Jedec files of the CC FDC, I have ordered the two PAL chips to a TI-99 user. Edited April 1, 2018 by fabrice montupet Quote Link to comment Share on other sites More sharing options...
+Ksarul Posted April 2, 2018 Share Posted April 2, 2018 No problem at all--one can always hope that an unlocked set of them turns up someday. It is sort of strange that I've been hunting PAL data today and turned up something else that I've been looking for in that area. It seems that Paolo Bagnaresi did a complete disassembly of an unlocked set of PALs for the Myarc FDC back in the nineties. I had a document to that effect (the Hardware Compendium, pulled down from WHT), but had completely missed that particular chapter as it wasn't a subject I was busy researching at the time I downloaded my copy. I spent much of a year trying to track down a version of that PAL (and was able to obtain a copy of the latest version from SNUG), and it turns out I had something I probably could have used to regenerate it all along. . . Quote Link to comment Share on other sites More sharing options...
fabrice montupet Posted April 2, 2018 Share Posted April 2, 2018 By my side, all is not lost. The PAL chips that I have received are copies of the originals, so I suspect that they are not protected. I just have to buy a IC programmer that accepts 12L6 PALs (the one I own only recognizes EPROMs, EEPROMs, PICs, PLDs and GALs but no 12L6). Thereupon, if you have a PAL programmer model to recommend me, tell me :-) Quote Link to comment Share on other sites More sharing options...
+Ksarul Posted April 2, 2018 Share Posted April 2, 2018 I have an Advin Pilot that will program and read pretty much any of the older PAL chips out there. Disadvantage to that one is that it requires direct access to a parallel port, so it doesn't work on the newer Windows operating systems. I use mine with an off-network Windows 2000 box. Unfortunately, none of the newer programmers I've tested will program the older chips (MiniPro, Topwin, Xeltek). Quote Link to comment Share on other sites More sharing options...
fabrice montupet Posted April 2, 2018 Share Posted April 2, 2018 none of the newer programmers I've tested will program the older chips (MiniPro, Topwin, Xeltek). This is my problem, and why I asked which programmer can do the job, maybe I will be able to buy one, and whatever the computer needed: I have all old generation of PC computers (8088/86,286,386,486, Pentium I/II/III/... and all others ) 2 Quote Link to comment Share on other sites More sharing options...
atrax27407 Posted April 3, 2018 Share Posted April 3, 2018 Here is a cross reference for PAL/GALs. The MiniPro will do GAL16V8s PAL Cross Reference.pdf 2 Quote Link to comment Share on other sites More sharing options...
fabrice montupet Posted April 3, 2018 Share Posted April 3, 2018 I have a programmer that also accepts many GAL chips including the Lattice GAL16V8 . But, if it can write this GAL in PAL mode (I have already done), it can't read a PAL chip directly :-( I had the confirmation that the TL866 will not work for reading the PALs. Quote Link to comment Share on other sites More sharing options...
marc.hull Posted April 4, 2018 Share Posted April 4, 2018 By my side, all is not lost. The PAL chips that I have received are copies of the originals, so I suspect that they are not protected. I just have to buy a IC programmer that accepts 12L6 PALs (the one I own only recognizes EPROMs, EEPROMs, PICs, PLDs and GALs but no 12L6). Thereupon, if you have a PAL programmer model to recommend me, tell me :-) Who supplied you with the PALs? Quote Link to comment Share on other sites More sharing options...
fabrice montupet Posted April 4, 2018 Share Posted April 4, 2018 Michael Becker :-) Quote Link to comment Share on other sites More sharing options...
atrax27407 Posted April 4, 2018 Share Posted April 4, 2018 Jim, It looks like you will have to "ping" Michael again. Quote Link to comment Share on other sites More sharing options...
fabrice montupet Posted April 4, 2018 Share Posted April 4, 2018 A few years ago, Michael has done a big clean-up of his basement. Not sure he still has these PAL chips. By my side, I do all my best to find a compatible programmer to read the PALs. 1 Quote Link to comment Share on other sites More sharing options...
marc.hull Posted April 4, 2018 Share Posted April 4, 2018 I don't think anyone really is worried about the ICs. It's the equations that are after. Quote Link to comment Share on other sites More sharing options...
atrax27407 Posted April 5, 2018 Share Posted April 5, 2018 If you can read the ICs, you have the equations. Quote Link to comment Share on other sites More sharing options...
marc.hull Posted April 5, 2018 Share Posted April 5, 2018 Not sure you actually can do that. Limited information I could find. If you know more then please expand. My point is that "if" MB programmed these replacements then obviously he has the info and probably much more. There's your resource. 1 Quote Link to comment Share on other sites More sharing options...
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