Jump to content

RickyDean

Members
  • Content Count

    1,524
  • Joined

  • Last visited

Everything posted by RickyDean

  1. Gonna try to do something similar to the 74ls139 for the flash chips, but if not, then a daughter board for the sound chip and 139, then they can be changed at will if there is an issue with them. Shucks, I'm cutting 7.1 inches out of a 4x4 Ford Excursion frame, then going to place a 05 Chevy Avalanche body on it with the Avalanche engine and a HD Chevy 4x4 transmission and Transfer case. Full leather, Navigation, and sun roof. NICE looking 2wd truck as it is. Keeping busy for sure.
  2. O @InsaneMultitasker, I am close to getting my sram project finished, but have a question or two. Then when finished I will continue getting the flash chips operational. In Fabrice's schematics it states " Solder the blue wire from pin #3 of the 74ls138 to the pin #40 of the gate array (AMD signal). But in the 512 doc from Chicago Faire it states "Pin 3 (LS138) to Gate Array pin #42 [Blue]. I have a red wire going to pin 40 not 42, that went to pin 3 (ls138). discrepancy or another way? Also the 1k resistor does it go between 20 and 28 on the 28 pin original sram location? And if you look at some of my prior pics, Geneve backside, the red wire was tied to a 1k resistor at pin 27 along with a white wire. Does that belong there? Thanks for helping.
  3. @GDMike, what Berry is trying to get across is that a few weeks ago, you were stating that you may have video issues. You said you were going to have someone look into it. The Geneve uses video memory as disk buffers, so if there is a video issue then the disks hard, floppy, or whatever, will not work correctly. The Geneve must be working, include video, to boot from any device. If that is not resolved then you can let the Geneve set on the shelf for 15 years and it still will not boot, no matter how up to date the process is. You haven't said that the video is fixed, if there ever was a problem to begin with and that is frustrating the diagnosis process. Hope my 2 cents helped.
  4. That is your decision, and you have produced an exceptional piece of work here, so I would be happy either way.
  5. Should we have a battery on board, Jim? Schmitzi and I talked about his batteries in a thread a couple of years ago. Mine never had one, as someone in the past removed it. Never used the card, so don't know if it is necessary?
  6. Ok!! Back in business, got my diodes in and started putting my little plan into action. Got this far, just need to connect wires to the pins of the sockets and then, if all goes well, sram!!. I am doing this to be able to replace the 512 sram or the 134 chip if one or the other fail. Plug and repair.
  7. @Schmitzi, are you trying to format a 3rd mfm hard drive on a hfdc? You have hds1, 2, 3? If so, you cannot format the third drive on a hfdc, as that drive is read only. You have to format the drive on 1 or 2, then place it on 3 to read from, you cannot write to it at all, unless something changed over the years or I'm misunderstanding something.
  8. Have you tried the f18a on just a vga monitor? If the screen looks crisp and clear then I would say it is a converter issue. I recently got my f18a and it looks good on its intended target a vga monitor, I will have to see how it performs on one of my HDMI converters.
  9. I have take this back. The socketed ones are ones I did long ago and to use the f18a, you have to stack another socket at the video chip. So it can be done, but may not fit in the case or be stable. It does work though on a board outsid ed of a case. Sorry for the confusion.
  10. Well your probably right. I do have 4 or 5 boards that have sockets, and I may have made that happen 20+ years ago, so mine may be the "lot". Sorry.
  11. No alot of TI's have socketed 9901's, from the factory.
  12. You could use one of the keyboard solutions, usb, ps2 keyboard, or rave 99 keyboard interface, to use in a arcade system, that you could either set in a rack out of the way on the side or unplug entirely if the game were joystick only. This would mean having a port somewhere in the cabinet to plug into.
  13. I can read out the 3.1 corcomp ramdisk firmware, have two of the 512's. Be later tonight.
  14. @atrax27407 probably has this eprom, his rates for a burned eprom are reasonable. He guarantees to give you a good eorom. Fyi.
  15. Schmitzi, this o ly updates the .98 to boot from ide and tipi. Your 1.00 will not do that . But there may be a 1.01 version that will, that's up to the dev team to decide. Hope this helps.
  16. Yea, someone just advertised a ti994a, on FB marketplace for 250.00. Just a basic system with 17 cartridges, no PEB. Ludicrous.
  17. Thanks, @Fritz442, I will try the set for the corcomp controller soon. I hope my eprom burner will allow me to burn pals and gals.
  18. If you take 512k (the dram chips on the left side of the board) from 640, you have 128k, which I believe, is the video memory, which is the 4 dram chips under the video chip. I think the first 32k sram chip next to the eprom is used by the cpu. Nor sure where it comes into the total memory picture, but to use later versions of mdos, it was necessary to stack another 32k on top and add a wire. The 384k mod takes all this into it's construction. The Insane one can explain it better probably.
  19. The 384k sram has that 32k built into it. So you could see it as 32k + 352k, though it is all contiguous memory. The Geneve has a 32k sram chip next to the eprom, then you would add the extra 32k on top to run the newer mdos's, but the 384k sram does that and more.
  20. I have wait till I get the diodes, called out in Fabrice's 384k mod, will run this on mine when I get it finished, but may be a week or two. Do have the rest of the BOM and my home built pcb's for continued work though.
  21. I feel that one of the members here, that has the ability to upate WHTECH, would be glad to do so. But if not, then here would be fine. My 2 cents.
  22. I was thinking of this too, don't use a recorder so don't know where these links were, but it's good not to rehash this again.
×
×
  • Create New...