Brian, you are absolutely correct. You sent me everything I possibly needed to understand how this should work and I managed to ignore some of it.
I really, really appreciate all your help. I’m just pumped that both DVI’s work when for a while I thought neither did. I will check the disk to see if has the 200 files on it, although I don’t have plans to get a T200. I had one a few years ago and sold it. Thanks again! Randy > On Feb 19, 2018, at 2:42 AM, Brian White <[email protected]> wrote: > > The manual, which is on-line btw, does mention somewhere in there that the > first step loads software from the disk to the dvi. Then the 2nd step loads > from the dvi to the M100. It also shows the backup procedure and all kinds of > other stuff. > > Also, 3 observable things do happen when the M100 is loaded successfully, > it's just that none of them obviously look like "Everything worked, we're > ready." > > 1) The M100 menu screen blanks and redraws. > > 2) The free memory display on the M100 menu reduces by about 5K. > > 3) The TV screen clears. The the Microsoft/Tandy boilerplate goes away > leaving only a cursor. > > I should have thought to ask if you saw these in the first place. I did say > "nothing happens" but that still isn't good enough because how could you know > what counts as "something" when it's just things like that? > > Though, I believe this is all in the video I posted. Did I ever post a link > here? I don't remember, maybe I only posted that to facebook... > https://youtu.be/Mt6AmyLKkXQ <https://youtu.be/Mt6AmyLKkXQ> > Not wait, I did post it here because didn't you point out that it looked like > I was using the serial port? So you saw the entire boot process. So you have > no excuse after all :) > > The service manual is also on-line which describes even more about how the > dvi works. > > http://www.classiccmp.org/cini/pdf/Tandy/Disk%20Video%20Interface%20Manual.pdf > > <http://www.classiccmp.org/cini/pdf/Tandy/Disk%20Video%20Interface%20Manual.pdf> > > http://www.classiccmp.org/cini/pdf/Tandy/Disk%20Video%20Interface%20Service%20Manual.pdf > > <http://www.classiccmp.org/cini/pdf/Tandy/Disk%20Video%20Interface%20Service%20Manual.pdf> > > It went similar with me. I thought I had 2 dead DVIs and 3 bad original > system disks, Then it turned out I had 2 good dvis, 3 good original system > disks, and merely one bad drive in one dvi. But I also had an unconfirmed > cable I made myself too, not one anyone else claimed was correct and tested. > I had no reason to believe I had it wired right. Now after finding some 360K > drives on ebay and finding just enough documentation on-line to set the > jumpers right, I have 2 fully working dvis, with 2 drives each no less. > > Now the last thing is, does your system disk contain files with 200 in the > name, like FMT200 and BAK200 ? And if not, do you have or plan to have a 200? > There are two versions of the system disk. One is for 100 & 102 only, the > other is for 100, 102, & 200. If you don't have the 100/200 system disk I can > make a copy. > > -- > bkw > > On Feb 18, 2018 6:31 PM, "Randall Kindig" <[email protected] > <mailto:[email protected]>> wrote: > Wow, I hooked up the original DVI box now that I know how all this works, and > since I verified the cable/M100/boot disk combination that works. > > Guess what, it works too!! > > I think what was throwing me was that when you reset the M100, the disk light > on the DVI doesn’t even come on most times. You just hear a very brief disk > noise from it, a second or two, and that must be all it takes to load the > DISK BASIC. You then go into BASIC on the M100, type SCREEN 1,1 and voila! > > I had originally assumed the disk drive light would come on and that it would > take several seconds to load DISK BASIC, so I was looking for that behavior. > > I now have a preponderance of riches. Two working DVI boxes. I’ll probably > sell a fully tested system on eBay with cable, boot disk, M100, DVI and > recover some of the funds I spent on all this. > > Thanks to everyone who helped with this. Especially you, Brian. I owe you > that beer :) > > Randy > > > >> On Feb 18, 2018, at 5:45 PM, Randall Kindig <[email protected] >> <mailto:[email protected]>> wrote: >> >> This worked perfectly, Brian! I now have a backup system disk and both have >> the write-protect tab on them. >> >> thanks! >> >> By the way, the system is consistently booting now. Just had to shake the >> dust off of it, I guess. >> >> Still would like to see if I can get the other DVI box working. >> >> Randy >> >> >>> On Feb 17, 2018, at 10:24 PM, Brian White <[email protected] >>> <mailto:[email protected]>> wrote: >>> >>> The easiest way is using the backup program on the system disk. >>> >>> It's possible but I think it's probably more difficult with a modern pc. I >>> don't think just any modern floppy controller chip can do it, and you need >>> a 360K drive too, ideally, not the more common 1.2M drive. Then you also >>> need special formatter software, which I don't know how available that is >>> today, and don't know if it would work from dosbox or something. Might have >>> to make a freedos bootable usb stick just to run the disk writing util. >>> >>> Steven Adolf has some notes on all that on club100 in the member uploads. >>> >>> It's much simpler to just use "BACKUP.SNG" in your case right from the >>> system disk. >>> >>> You would boot the dvi normally, then go into basic and: >>> >>> RUN"0:FORMAT" >>> >>> Then follow the prompts to remove the system disk and put in a disk to be >>> blanked and formatted. >>> >>> Then put the system disk back in and: >>> >>> NEW >>> RUN"0:BACKUP.SNG" >>> >>> Then follow the prompts to switch back and forth putting the new disk in, >>> then the system disk, then the new one again, etc, until it's over. Choose >>> All when it asks All or System. >>> >>> I would definitely put tape over the write-protect notch on your one >>> remaining working system disk before any of this! >>> >>> -- >>> bkw >>> >>> On Feb 17, 2018 9:19 PM, "Randall Kindig" <[email protected] >>> <mailto:[email protected]>> wrote: >>> I will check that, Brian. Thanks for your help. >>> >>> My other question is around the boot disk. I was sent 2 boot disks with >>> the cable, but now only 1 seems to work. I’m worried now only having one >>> working disk. >>> >>> How do I back it up? Is there a way to do that with the DVI? Can I create >>> one in a different disk drive, like the drive in the TRS-80 Model 4P? >>> >>> thanks >>> >>> Randy >>>> On Feb 17, 2018, at 9:15 PM, Brian White <[email protected] >>>> <mailto:[email protected]>> wrote: >>>> >>>> This sounds consistent with Fugu's idea about old capacitors. It sounds >>>> like both dvi's are marginal, but one is slightly better than the other, >>>> and one of your M100's is slightly better than the other, and so with the >>>> two best ones combined, it just barely works, sometimes. >>>> >>>> I would check that voltage as he described and I expanded. >>>> >>>> On Feb 17, 2018 8:37 PM, "Randall Kindig" <[email protected] >>>> <mailto:[email protected]>> wrote: >>>> SUCCESS! >>>> >>>> Per John’s suggestion (and was thinking the same thing when he suggested >>>> it) I now have a working system. I started trying different combinations >>>> of DVI/M100/cable (of which I have 2 each). >>>> >>>> DVI #2, M100 #2, Cable #2, no luck >>>> >>>> So I swapped out M100 #2 (32K) for M100 #1 (24K/REX), and it worked! >>>> >>>> It’s still a little finicky and doesn’t always work, but has worked >>>> multiple times now. I don’t know if there’s anything I can do to “tune” >>>> it so it’s more consistent, but I”m pumped that I finally got it to work. >>>> >>>> I had tried this M100/cable combination with DVI #1, so I’m wondering if >>>> there’s an issue with that DVI. There also must be an issue of some sort >>>> with M100 #1 as the current DVI/cable setup didn’t work with that machine, >>>> but does with the other. >>>> >>>> This sure seems like a finicky setup. I would love to see a modern DVI >>>> replacement, perhaps with SD card for disk and video output, that would >>>> take up far less desk space and be more robust. >>>> >>>> Thanks all! Any other suggestions for troubleshooting why the M100 (#2) >>>> doesn’t work with this and also why DVI #1 doesn’t work with either M100 >>>> would be much appreciated. >>>> >>>> Randy >>>> >>>> >>>> > On Feb 17, 2018, at 4:22 PM, Randy Kindig <[email protected] >>>> > <mailto:[email protected]>> wrote: >>>> > >>>> > I was just thinking the same thing John. It’s worth a try. >>>> > >>>> > Thanks >>>> > >>>> > Sent from my iPhone >>>> > >>>> >> On Feb 17, 2018, at 3:07 PM, John R. Hogerhuis <[email protected] >>>> >> <mailto:[email protected]>> wrote: >>>> >> >>>> >> Btw it occurs to me that there are 16 permutations possible there. Not >>>> >> so high that you couldn’t do all 16 and see if you ever get different >>>> >> results in any of 16 if you haven’t already. >>>> >> >>>> >> — John. >>>> >>> >> >
