No problem of course. It's nice to think of another couple units working and another couple people learning how something old worked and carrying it forward another few years.
-- bkw On Feb 19, 2018 9:11 PM, "Randall Kindig" <randall.kin...@gmail.com> wrote: > 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 <bw.al...@gmail.com> 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 > 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" <randall.kin...@gmail.com> > 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 <randall.kin...@gmail.com> >> 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 <bw.al...@gmail.com> 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" <randall.kin...@gmail.com> >> 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 <bw.al...@gmail.com> 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" <randall.kin...@gmail.com> >>> 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 <randall.kin...@gmail.com> >>>> 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 <jho...@pobox.com> >>>> 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. >>>> >>>> >>> >> >> >
