TI-GAMER Posted June 16, 2015 Share Posted June 16, 2015 (edited) I received my MG EPROMs to upgrade my Corcomp Disk Controller and when I opened it up I noticed that Bank 1 and 2 appear to be reversed from other CorComp Cards that I have seen in photos. Before I perform the upgrade I just wanted to verify that they are going in the correct sockets. My CorComp Card is showing Bank 1 to be more towards the middle of the board where as the others I have seen show it being towards the outer edge of the card. My board seems reversed. I am assuming its correct unless someone put the stickers on the wrong chips. I am including a photo of my board (Dark Green) and the other board (Stock Photo). Can anyone verify this? Thank You Edited June 16, 2015 by TI-GAMER Quote Link to comment Share on other sites More sharing options...
+Schmitzi Posted June 16, 2015 Share Posted June 16, 2015 hmmm, not sure, but I could imagine that somebody just had confused the stickers. Quote Link to comment Share on other sites More sharing options...
+Ksarul Posted June 16, 2015 Share Posted June 16, 2015 Notice the controller chip in yours--it is a WD2793. That, plus the date of your ROMs, makes it one of the earliest revisions of the CorComp controller (and validated by the Gray case--they only used those on the very early cards). There are a lot of differences between the layout of that board and later ones using the WD1773 (although the ones with the WD1773 on a little daughter board are the same layout as yours too). CorComp changed chips mid-stream due to receipt of a bad lot of 2793 chips. Good 2793s were almost impossible to obtain for a while. They tested each of the chips from the lot of bad chips (something like one in ten was good, IIRC), and put those in the boards. When they ran out, they put a daughter board into the socket using the software-compatible WD1773 chip (it wasn't pin-compatible, which was the reason for the daughter board). They then just stayed with the WD1773 in the later board revisions. . . All that to say, the labels might just be right. The chips won't do anything if they are in the wrong sockets--the DSR just won't work right. Try it using the positions of your original chips, and if it doesn't work, swap them. Just make sure that pin one is in the right spot each time. . . 1 Quote Link to comment Share on other sites More sharing options...
TI-GAMER Posted June 16, 2015 Author Share Posted June 16, 2015 Great! Thank you for the detailed information. Will I have any issues with the MG Update in this older card? Quote Link to comment Share on other sites More sharing options...
+Ksarul Posted June 16, 2015 Share Posted June 16, 2015 None at all--as I noted, the two chips are software compatible. I think I have a set of them in my CorComp with a 2793 chip in it as well. . . Quote Link to comment Share on other sites More sharing options...
+mizapf Posted June 16, 2015 Share Posted June 16, 2015 Here are the pictures I took of two CorComp controllers just a few days ago: http://www.ninerpedia.org/index.php/Floppy_Disk_and_Hard_Disk_Controller_Cards#CorComp_Double-Density_Floppy_Disk_Controller 1 Quote Link to comment Share on other sites More sharing options...
TI-GAMER Posted June 16, 2015 Author Share Posted June 16, 2015 The MG EPROMS are now installed. It was a piece of cake but I wont get a chance to test the card for another 24 - 48 hours. Quote Link to comment Share on other sites More sharing options...
Mad Hatter Posted June 17, 2015 Share Posted June 17, 2015 What exactly does the MG upgrade add to the card? Quote Link to comment Share on other sites More sharing options...
Opry99er Posted June 17, 2015 Share Posted June 17, 2015 (edited) IIRC, it removes the system-takeover "feature" of the card, for one... Also fixes some punchy DSR conflicts. Edited June 17, 2015 by Opry99er Quote Link to comment Share on other sites More sharing options...
Omega-TI Posted June 17, 2015 Share Posted June 17, 2015 ...but I wont get a chance to test the card for another 24 - 48 hours. Quote Link to comment Share on other sites More sharing options...
TI-GAMER Posted June 17, 2015 Author Share Posted June 17, 2015 The Miller's Graphics enhancement of the FDC chip which adds some CALLs and eliminates the startup screen and problems it created. Quote Link to comment Share on other sites More sharing options...
+arcadeshopper Posted June 17, 2015 Share Posted June 17, 2015 What exactly does the MG upgrade add to the card? ftp://ftp.whtech.com/datasheets%20and%20manuals/Hardware/Millers%20Graphics/mg%20eprom%20for%20corcomp%20controller%20manual.pdf Quote Link to comment Share on other sites More sharing options...
+Schmitzi Posted August 6, 2015 Share Posted August 6, 2015 Hi, I have the CC-9900-FloppyController 1985-Rev.A (Eproms swapped, #1 on the left side. #2 on the right) The controller is running very fine, already did a lot of work with it, and now, nosy as I am, I have tried the upgrade with the MG-Eproms, but this does not want to run I see the "DOS © 1986 Miller Graphics" on the top of the startscreen, correct, as mentioned in the MG-manual. When I am "Ready - and press any key to begin", I get the standard menue with my cartridge present (not the CC-Menue, of course) TI-Basic starts, but no access to any floppydrive ExtendedBasic, as an example, or Diskmanager II , the controller LED goes on, stays on, and the system just runs and hangs in a blue screen (not that from Win-NT) Do you have any ideas ? Maybe bad eprom-chips, or bad BIN-files (v8.9) ? or anything else ? I have also tried some other drives, also a lonely 90K-standard-one from TI...no gain The big mitigation is, I have swapped back the original Eproms, and the world is OK now any ideas welcome thanks a lot schmitzi Quote Link to comment Share on other sites More sharing options...
Fritz442 Posted August 6, 2015 Share Posted August 6, 2015 (edited) The big mitigation is, I have swapped back the original Eproms, and the world is OK now Has to be the Eproms or an incompatible set... Edited August 6, 2015 by Fritz442 1 Quote Link to comment Share on other sites More sharing options...
+Schmitzi Posted August 6, 2015 Share Posted August 6, 2015 ah OK, one more try for me thanks. incompatible sets, does it mean the BIN-files, or the Eprom-chips, too ? Quote Link to comment Share on other sites More sharing options...
Fritz442 Posted August 6, 2015 Share Posted August 6, 2015 (edited) ah OK, one more try for me thanks. incompatible sets, does it mean the BIN-files, or the Eprom-chips, too ? Probably one or the other. I would lean to incompatible bin. If you have an easy/convenient way to write the Eproms, I would clear and rewrite the new Eproms with the original DSR data to test the chips. If it works ok, you know it's the new bins and your not spending any money only a little time. Edited August 6, 2015 by Fritz442 1 Quote Link to comment Share on other sites More sharing options...
+Schmitzi Posted August 6, 2015 Share Posted August 6, 2015 perfect, I´ll try that. thanks Quote Link to comment Share on other sites More sharing options...
Gazoo Posted August 6, 2015 Share Posted August 6, 2015 You might also have them reversed. 2 Quote Link to comment Share on other sites More sharing options...
+Schmitzi Posted August 7, 2015 Share Posted August 7, 2015 Hi Gazoo, "reversed" means, the Eprom-No.1 onto the right socket, like all non-1985-Rev.A-Boards ? I didn´t try that as I got this correctly message "DOS © 1986 Miller Graphics" on the top of the startscreen and I was a bit anxious to test swapping that chips... but of course, you are right, what should happen.... thanks Quote Link to comment Share on other sites More sharing options...
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