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 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%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]> 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]> > 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]> 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]> > 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]> 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]> >> 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]> >>> 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]> >>> 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. >>> >>> >> > >
