My new cable is like you say on the right. ----
* The Model 100 tech ref http://www.classiccmp.org/cini/pdf/Tandy/Model%20100%20Tech%20Reference.pdf page 28 (also the service manual http://www.classiccmp.org/cini/pdf/Tandy/Model%20100%20Service%20Manual%20(Final).pdf page 35) Says, for instance, AD0 is pin 3 * The DVI service manual http://www.classiccmp.org/cini/pdf/Tandy/Disk%20Video%20Interface%20Service%20Manual.pdf page 70 Says AD0 is pin 6 ---- Similarly, I've now built a T102 cable with the twists. https://photos.google.com/share/AF1QipMkzQNqSYNaG6XGROBssfEmXJ5kj3-Kv-gOHMuqPQJdSUloL8ZpSs83D-tcocw8jA?key=ZzRJQnlPVXlsRVZJVGE1ZXlKdkpoYnlvTUh0NjhB * The T102 tech ref http://www.classiccmp.org/cini/pdf/Tandy/Model%20102%20Tech%20Reference.pdf page 20 Says AD0 is pin 5. And sure enough, this cable constructed this way, pin 5 on the T102 end goes to pin 6 on the DVI end. This cable visually matches up with the old ebay one too, which we can only assume was good. (I didn't buy this cabel, just downloaded the pics while the ad was still up) https://goo.gl/photos/Sm8xx3Ys2vJwpQYu7 ---- To me this corroborates the M100 cable, because it shows that both cables deliver the same signal to the same pin at the DVI end, and I think there is no argument about how to make a T102 cable, and this T102 cable also appears to agree with the tech references. Everything is consistent with everything else. This also reasserts my initial idea that they designed the DVI pinout specifically to accommodate the fact that the DIP connector connects to different pins than regular IDC connectors (setting aside the different numbering pattern for dip vs pin headers), specifically to allow a flat simple cable using a dip connector like the one I have, and the other ones I found on other sites where the data sheet explicitly showed the "pin 1 to wire 2" note, and why the T102 needs twists. I've now tried both my M100's and my T102, and none of them are booting my dvi, but by now, I actually think it's a problem with the dvi even though these cables are both new and unproven. The pinouts check out with the manuals, my new T102 cable also agrees visually with those pics from that old ebay item for a T102 cable. I got my dvi off ebay and never saw it actually work, nor did the seller claim it. -- bkw On Tue, Oct 24, 2017 at 1:00 AM, Mike Stein <mhs.st...@gmail.com> wrote: > I must admit that I'm starting to get confused myself but unless I hear > otherwise I'm going to stick with my original opinion (Oct 17) that the DIP > pin 1 should connect to the IDC header pin 1 which would connect DIP 29 to > header 24, not 23. Sounds like your cable connects DIP 1 to Header 2 etc. > > > Correct ? Yours? > *DIP* *IDC* *DIP* *IDC* > *1* *1* *1* *2* > *2* *3* *2* *4* > *3* *5* *3* *6* > *4* *7* *4* *8* > *5* *9* *5* *10* > *6* *11* *6* *12* > *7* *13* *7* *14* > *8* *15* *8* *16* > *9* *17* *9* *18* > *10* *19* *10* *20* > *11* *21* *11* *22* > *12* *23* *12* *24* > *13* *25* *13* *26* > *14* *27* *14* *28* > *15* *29* *15* *30* > *16* *31* *16* *32* > *17* *33* *17* *34* > *18* *35* *18* *36* > *19* *37* *19* *38* > *20* *39* *20* *40* > *21* *40* *21* *39* > *22* *38* *22* *37* > *23* *36* *23* *35* > *24* *34* *24* *33* > *25* *32* *25* *31* > *26* *30* *26* *29* > *27* *28* *27* *27* > *28* *26* *28* *25* > *29* *24* *29* *23* > *30* *22* *30* *21* > *31* *20* *31* *19* > *32* *18* *32* *17* > *33* *16* *33* *15* > *34* *14* *34* *13* > *35* *12* *35* *11* > *36* *10* *36* *9* > *37* *8* *37* *7* > *38* *6* *38* *5* > *39* *4* *39* *3* > *40* *2* *40* *1* > > m > > ----- Original Message ----- > *From:* Brian White <bw.al...@gmail.com> > *To:* m...@bitchin100.com > *Sent:* Monday, October 23, 2017 10:11 PM > *Subject:* Re: [M100] DVI cable > > My order from Phoenix came in. > http://www.king-cart.com/phoenixent/product_name=HWS15322 > http://www.king-cart.com/phoenixent/product_name=HWS1877 > http://www.king-cart.com/phoenixent/product_name=HWS16014 > > I have determined that: > > * The DIP connector above IS the kind that connects pin1 to conductor2. > > * If you crimp the two connectors above straight-through with no twisting > pairs of wires or other tricks to get the pinout flipped, that results in a > cable with the right wiring, at least according to the tech/service manuals > for both M100 and DVI. > > I have some pictures here so you could make the cable by just visually > matching up the orientations of the connectors and cable: > http://tandy.wiki/Disk/Video_Interface > > One of the pictures there is I took the bus pinout drawings from both > manuals, and added another drawing for dip40 for the m100 side, so you can > easily figure out or verify a cable, ignoring any theories about flipping > pairs or which way the cable should go into a connector etc, you just go > from pin to pin, by number, with the drawings for the connectors so you > know which pin actually is pin6 on both connectors etc, so you can match up > the *signals*. for certain. > > So I have verified that these parts crimped this way, results in a cable > that for example, pin 29 on the Model 100 goes to pin 23 on the DVI. > (The WR pin goes to the WR pin.) Same for everything else. > > HOWEVER > > I can't say I actually used it successfully. I followed the boot sequence > in the DVI manual and the DVI presents the first two prompts on my monitor, > the disk drive makes a noise briefly, the disk drive light comes on, all as > the manual says to expect. But when I insert my boot disk and close the > door latch, nothing ever happens. > > My boot disk is an original not a copy, so it might be corrupt from age > but at least I know it's not simply mis-labeled or a bad copy. > > I still have another M100 and a T102 I could try, including a home-made > T102 cable that came with the unit. (someone butchered it out of an IDE > cable.) > > One symptom that shows something somewhere is wrong, is that when I turn > on the dvi, usually the m100 does something bad. Sometimes the M100 screen > goes blank, sometimes it simply freezes (the clock stops counting), > sometimes 2 or 3 of the character cells on the M100 screen get scrambled. > > With the dvi cable unplugged and then cold-start, the M100 behaves normal > and seems to work fine, and displays the same free ram. > I haven't verified that the system bus is still functional, but I can. I > have a PG Designs 8-bank ram upgrade that goes in a M100 bus connector. > > The M100 even acts normal after a cold-start even with the cable and dvi > connected, before turning the dvi on. > > -- > bkw > >
