Tom, The cables that Brian is recommending will attach to your existing usb to serial adapter. So the connection would work as follows.
Laptop USB Port -> USB to Serial Adapter -> DB9 to Db25 Null modem Cable -> Model T Kurt On Wed, Apr 10, 2019, at 9:46 AM, Thomas Morehouse wrote: > Thanks Brian. Turns out your cable links weren't in my thread at all. They > were in a different thread completely which I wasn't part of, and wasn't > following. > > Here's the situation. Those two cables you recommend in that other thread are > null modem cables. Fine - but I've already learned the problem I have is with > my usb/serial cable. Soon as I plug it into the 102, the 102 screen dims, > which may be caused (I've been told) by crossed wiring in that cable. > > So, even if I do buy another cable (one of the null modem cables), I'd still > need some kind of usb/serial "converter/adapter". There's no usb on the > recommended null modem cables, and there's no serial port on the Dell laptop > or desktop. > > Thanks. > Tom M. > > > On Wed, Apr 10, 2019 at 12:39 PM Brian White <[email protected]> wrote: >> In one post, I provided a link directly to two items, a specific cables2go >> cable and a specific sabrent usb-serial adapter, so that you wouldn't have >> to make sense of the full page where that info came from. >> >> And also linked that full page, which includes the startech and others. >> >> http://tandy.wiki/Model_100_102_200_600_Serial_Cable >> >> I know reading that full page might not make 100% sense, because it's a lot >> of verbiage, and there are many cables listed there and they all work for >> this so how do you choose, and some parts are kind of cryptic, which is why >> I pulled out the two parts to get. >> >> For instance the shorthand I used to document each cables wiring >> idiosyncracies, like "DCD<>DSR+DTR", I know that part is cryptic. When I was >> testing cables and assembling the info, I just needed to get the key details >> written down, and the form didn't matter. I could expand it to be more >> readable later. >> >> What those little things are showing is how each particular cable differs >> from the rs232 spec. >> >> For instance "DCD<>DSR+DTR" means that dsr and dtr are tied together on one >> end, and connected to dcd on the other end, and that it's the same on both >> ends in both directions. All other connections are according to the rs232 >> spec, and you get the pin numbers and positions from the rs232 spec. >> >> Some time when I want to spend more time on that page, I can expand those to >> a less cryptic form, (or anyone else can, it' s a wiki) but until then at >> least the knowledge is documented so that later I can refer to it. It's sort >> of like working notes until then. >> >> Mike Stein also provided a direct link to a specific monoprice cable. That >> one is good too. (it's on that page too for instance) >> >> All other cables you randomly find from wherever, probably aren't right >> without some kind of adapters, and there is no way to tell if the wiring is >> right except by knowing the rs232 spec and testing the connections. >> >> rs232 is not a single thing, it's a spec with a bunch of options and >> configurations. In order to use anything serial, you the user, actually has >> to understand that spec, or, you have to take the word of someone else who >> does, and says "this specific cable will work for this specific >> application". Plugging in any old cable without knowing how it's wired or >> what the different rs232 signals are for and how they work, will never work. >> Serial is not like usb or ethernet or headphones. >> >> For another example of ehat I mean, even when you finally get a correct >> serial cable for connecting your m100 to a pc, that cable won't be correct >> for connecting to a modem, or a plotter, etc. 3 different devices, 3 >> different cables, and yet all of them are valid correct serial cables even >> though they are all different from each other. >> >> The only way to make it work is to understand that and go read about serial >> cables so that you know enough that you could build your own from scratch, >> or continuity test any off the shelf cable to fully understand what it does. >> Or, buy one that is already known to be correct for this particular task. >> >> -- >> bkw >> >> >> >> On Wed, Apr 10, 2019, 7:30 AM Thomas Morehouse <[email protected]> wrote: >>> Brian - you wrote: >>> >>> " >>> >>> The Cables2Go one I linked is all the same, except it also has rts/cts, >>> so it works with HTERM, as well as everything else. >>> >>> And finally, the StarTech one I linked, is also all the same, but >>> without shorting DCD to DSR, or shorting DTR to DSR, which means that >>> one should cause the least possible drain on any possibly weak power >>> rails in the M100. >>> >>> All this mystery has already been completely figured out and nailed >>> down. One mouse click and $7 later and you're done." >>> >>> I've gone through all your posts in this thread, and find no links for >>> Cables2go or StarTech. >>> >>> I'm absolutely going nuts here, trying to figure out how to do things, and >>> how to follow advice. One post with advice raises a question, someone else >>> tries to answer the question, then someone else tries to clarify the answer >>> to someone else's question. Really helpful to some, but frustrating to me. >>> >>> Which post had those two links for the proper cables? I've now got two >>> usb/serial cables which don't seem to work, plus several male/male, >>> female/female, and DB9 to DB25 adapters. Total so far: $100. >>> >>> As I can't find the links Brian referred to, I don't want to guess and buy >>> yet another thing which might not work. >>> >>> Thanks. >>> Tom M. >>> >>> >>> >>> >>> On Tue, Apr 9, 2019 at 9:34 PM Kurt McCullum <[email protected]> wrote: >>>> __ >>>> Tom, >>>> >>>> Looks like you will need to either build or buy a cable. My two cents is >>>> below but I'm sure others will chime in. There are several options out >>>> there. >>>> >>>> Here is a description of what I do with all my Model-T units. I start with >>>> this DB25 to DB9 adapter which is just a regular DB9 to DB25 converter. I >>>> attach these with some 2.5mm (should be 2.6mm) screws to the Model-T so >>>> its always attached. >>>> https://www.sfcable.com/db9-female-to-db25-male-serial-mini-adapter.html >>>> >>>> Then I put one of these adapters in between the DB9 serial port and the >>>> 9-25 adapter which creates a null modem cable. >>>> https://www.sfcable.com/null-modem-adapter-db9-db25/db9-male-to-female-null-modem-mini-adapter.html >>>> >>>> For my T200 I have remove pin 1 from the null modem adapter to make it >>>> happy but that's a quick fix with needle nose pliers. >>>> >>>> Everybody has there preference on cable setup so eventually you will come >>>> up with a solution that works for you. Sounds like what you have is >>>> working for text transfers so that's a start. >>>> >>>> Kurt >>>> >>>> >>>> On Tue, Apr 9, 2019, at 5:59 PM, Thomas Morehouse wrote: >>>>> Thanks Kurt. >>>>> >>>>> Testing the DB9-DB25 adapter only - not the usb/serial cable - I have >>>>> continuity NOT from pin 4 of the DB9 to pin 6 of the DB25. I have >>>>> continuity from pin 4 of the DB9 to pin 20 of the DB25. That's using the >>>>> numbers printed at the pins themselves. >>>>> >>>>> Should I even bother testing the others you suggest? Sounds like the >>>>> adapter already fails the test. >>>>> >>>>> Tom M. >>>>> >>>>> >>>>> On Tue, Apr 9, 2019 at 8:48 PM Kurt McCullum <[email protected]> wrote: >>>>>> __ >>>>>> Ignore the USB to serial piece of the puzzle. As Brian said, it's just a >>>>>> serial port. Test the 9 to 25 adapter. One end will be female so it's >>>>>> easier to put something like the end of a paper clip into one hole at a >>>>>> time then put the probe on that. >>>>>> >>>>>> Kurt >>>>>> >>>>>> On Tue, Apr 9, 2019, at 5:22 PM, Thomas Morehouse wrote: >>>>>>> OK - looks like I wasn't clear. In Kurt's post, he writes: >>>>>>> >>>>>>> "Take one probe of the meter and put it on pin 4 of the DB9 and the >>>>>>> other on pin 6 of the DB25. It should beep or light up (however you >>>>>>> meter functions to indicate a connection). Then do the same for the DSR >>>>>>> line on pin 6 to pin 20. And finally the RTS and CTS pins 7->5 and 8-> >>>>>>> 4. If they are crossed in some manner, then you will not get a beep or >>>>>>> a light." >>>>>>> >>>>>>> If the usb/serial cable is a single unit (usb at one end, DB9 at the >>>>>>> other), how do I put one probe of the meter on the DB9 and the other >>>>>>> probe of the meter on the DB25? There's no DB25 on the cable, unless I >>>>>>> plug the 9-25 adapter into the DB9 - but then I can't put a probe on >>>>>>> the DB9. Jeez I feel dense. >>>>>>> >>>>>>> I'm really sorry I can't follow this, but maybe I'm just overlooking >>>>>>> something really simple? >>>>>>> >>>>>>> Thanks. >>>>>>> Tom M. >>>>>>> >>>>>>> >>>>>>> On Tue, Apr 9, 2019 at 7:56 PM Brian K. White <[email protected]> >>>>>>> wrote: >>>>>>>> You don't check continuity on the usb-serial adapter. That isn't just >>>>>>>> a >>>>>>>> cable, it's really a peripheral like a disk drive or a printer, it >>>>>>>> just >>>>>>>> happens to be a peripheral that all fits entirely inside the plug >>>>>>>> housing on one end of it. There is no simple direct wire mapping >>>>>>>> between >>>>>>>> the usb pins and the serial pins. Between the usb pins and the serial >>>>>>>> pins, there is circuit board with a chip and a few other components >>>>>>>> which is converting and translatine between two entirely different >>>>>>>> kinds >>>>>>>> of signals and protocols. >>>>>>>> >>>>>>>> You treat the usb-serial adapter as just a serial *port*, and ignore >>>>>>>> that it looks like a wire. Just pretend it's like a serial port built >>>>>>>> in >>>>>>>> to the back of an old desktop. >>>>>>>> >>>>>>>> You check the continuity of the serial cable, which IS "just a cable". >>>>>>>> Or, really, you check the continuity of the combined serial cable with >>>>>>>> any null-modem and gender-changer adapters, and treat that all >>>>>>>> together >>>>>>>> as one "cable". >>>>>>>> >>>>>>>> -- >>>>>>>> bkw >>>>>>>> >>>>>>>> On 4/9/19 6:56 PM, Thomas Morehouse wrote: >>>>>>>> > Thanks Kurt. I'm even denser than usual tonight I guess. >>>>>>>> > >>>>>>>> > From earlier posts, seems the problem (102 screen dimming) is likely >>>>>>>> > caused by the usb/serial cable. One end of the cable is a usb plug; >>>>>>>> > other end is the DB9. >>>>>>>> > >>>>>>>> > So I'm afraid I don't know how to test continuity on the cable. I >>>>>>>> > can >>>>>>>> > find pin 4 of the DB9 - but where does the DB25 fit in the picture? >>>>>>>> > >>>>>>>> > Or, are you saying to test the cable with the DB9/DB25 adapter >>>>>>>> > plugged >>>>>>>> > into the cable? >>>>>>>> > >>>>>>>> > Sorry to be the dolt again. >>>>>>>> > Tom M. >>>>>>>> > >>>>>>>> > >>>>>>>> > On Tue, Apr 9, 2019 at 10:57 AM Kurt McCullum <[email protected] >>>>>>>> > <mailto:[email protected]>> wrote: >>>>>>>> > >>>>>>>> > There are store bought cables that work well. Brian has done a >>>>>>>> > great job putting together a list of those cables. For my machines >>>>>>>> > I have a mixture of custom made cables or slim adapters. Both >>>>>>>> > methods work and give me the pinout below. When you get the cable >>>>>>>> > right, your M102 will be happy. >>>>>>>> > >>>>>>>> > But to the question at hand, don't tear apart your cable. Check >>>>>>>> > it. Right now you know that pins 2,3 and 5 are all going to the >>>>>>>> > right locations. You will need to check pins 4,6,7 and 8. Since >>>>>>>> > those are paired lines (4/6, 7/8) one or both pairs will be flipped. >>>>>>>> > >>>>>>>> > If you have a multi-meter which has a continuity check on it then >>>>>>>> > you test both ends of the wire. >>>>>>>> > >>>>>>>> > Here is what I have found to work on all my machines and I include >>>>>>>> > this in the mComm manual. >>>>>>>> > >>>>>>>> > 7 Wire Cable >>>>>>>> > PC >>>>>>>> > >>>>>>>> > Model-T >>>>>>>> > DCD >>>>>>>> > 1 >>>>>>>> > NC >>>>>>>> > >>>>>>>> > >>>>>>>> > RX >>>>>>>> > 2 >>>>>>>> > → >>>>>>>> > 2 >>>>>>>> > TX >>>>>>>> > TX >>>>>>>> > 3 >>>>>>>> > ← >>>>>>>> > 3 >>>>>>>> > RX >>>>>>>> > DTR >>>>>>>> > 4 >>>>>>>> > ← >>>>>>>> > 6 >>>>>>>> > DSR >>>>>>>> > GND >>>>>>>> > 5 >>>>>>>> > ↔ >>>>>>>> > 7 >>>>>>>> > GND >>>>>>>> > DSR >>>>>>>> > 6 >>>>>>>> > ← >>>>>>>> > 20 >>>>>>>> > DTR >>>>>>>> > RTS >>>>>>>> > 7 >>>>>>>> > → >>>>>>>> > 5 >>>>>>>> > CTS >>>>>>>> > CTS >>>>>>>> > 8 >>>>>>>> > ← >>>>>>>> > 4 >>>>>>>> > RTS >>>>>>>> > RI >>>>>>>> > 9 >>>>>>>> > NC >>>>>>>> > >>>>>>>> > >>>>>>>> > >>>>>>>> > >>>>>>>> > Take one probe of the meter and put it on pin 4 of the DB9 and the >>>>>>>> > other on pin 6 of the DB25. It should beep or light up (however >>>>>>>> > you meter functions to indicate a connection). Then do the same >>>>>>>> > for the DSR line on pin 6 to pin 20. And finally the RTS and CTS >>>>>>>> > pins 7->5 and 8-> 4. If they are crossed in some manner, then you >>>>>>>> > will not get a beep or a light. >>>>>>>> > >>>>>>>> > Hope that makes sense. >>>>>>>> > >>>>>>>> > Kurt >>>>>>>> > >>>>>>>> > >>>>>>>> > On Tue, Apr 9, 2019, at 7:38 AM, Thomas Morehouse wrote: >>>>>>>> >> Thanks for the comments gents. Learn something every day. >>>>>>>> >> >>>>>>>> >> Kurt, on the "crossed wires" issue, what is the procedure for >>>>>>>> >> fixing the problem? I sure don't want to pull something apart, >>>>>>>> >> or buy even *more* adapters! >>>>>>>> >> >>>>>>>> >> Thanks. >>>>>>>> >> Tom M. >>>>>>>> >> >>>>>>>> >> >>>>>>>> >> On Tue, Apr 9, 2019 at 10:03 AM Kurt McCullum <[email protected] >>>>>>>> >> <mailto:[email protected]>> wrote: >>>>>>>> >> >>>>>>>> >> >>>>>>>> >> What you are describing happens to me when the either the >>>>>>>> >> CTS/RTS or DTR/DSR wires in your cable are crossed. >>>>>>>> >> >>>>>>>> >> Example. The CTS pin listens (checks for voltage) to the RTS >>>>>>>> >> pin on the other end. If you have a cable where RTS goes >>>>>>>> >> straight to RTS and CTS going straight to CTS, then you have >>>>>>>> >> two ends of the cable both feeding voltage to the same wire. >>>>>>>> >> This causes the screen to go dim. the DTR/DSR pins can >>>>>>>> >> produce the same issue. >>>>>>>> >> >>>>>>>> >> Kurt >>>>>>>> >> >>>>>>>> >> On Tue, Apr 9, 2019, at 5:33 AM, Thomas Morehouse wrote: >>>>>>>> >>> Now that I've got my usb/serial link working (M102 to Dell >>>>>>>> >>> laptop), I notice the 102's screen get quite dim when the >>>>>>>> >>> cable is in the 102's 25 pin serial port. >>>>>>>> >>> >>>>>>>> >>> Doesn't need to be connected to the Dell. Just when you plug >>>>>>>> >>> the usb/serial cable into the 102. Unplug the cable, 102 >>>>>>>> >>> screen returns to normal visibility. >>>>>>>> >>> >>>>>>>> >>> Something to worry about? or just live with it? I wouldn't >>>>>>>> >>> have thought the usb/serial cable chip would put such a >>>>>>>> >>> drain on the system. Happens with battery power, or even >>>>>>>> >>> with external 6 volt poweer. >>>>>>>> >>> >>>>>>>> >>> Thanks. >>>>>>>> >>> Tom M. >>>>>>>> >>> >>>>>>>> >> >>>>>>>> > >>>>>>>> >>>>>> >>>>
