Well maybe hold off then, because my plan is to document what I do. I don’t 
mind videos but there is a reason I maintain a tech blog for all the project I 
work on / build.



Sent from my iPad

> On 22 Sep 2020, at 7:11 pm, Jonathan Yuen <jonathan.y...@slu.se> wrote:
> 
> Hi,
> 
> I'll have to take a look.  Generally avoid videos because I'm too lazy to 
> take notes but I realize that recording a video is easier than writing stuff 
> and making web pages.....
> 
> Jonathan
> 
> jonathan.y...@mykopat.slu.se
> ________________________________________
> Från: M100 [m100-boun...@lists.bitchin100.com] för james.z...@gmail.com 
> [james.z...@gmail.com]
> Skickat: den 22 september 2020 10:54
> Till: m...@bitchin100.com
> Ämne: Re: [M100] definition of null modem
> 
> Buddy
> 
> Have you checked out youtube? I’m literally about to undertake a project that 
> sounds like what your after. I’m fitting a rpi zero into an old modem housing 
> and having it share the WiFi out over ppp serial. There are two very good 
> videos on this process which can be found on YouTube. One uses an Commodore 
> Amiga and the other is using a Win95 PC as the system they are trying to get 
> online. Both see the Rpi as a regular modem.
> 
> I hoping to get it working so I can recover email on my Amiga 500+
> 
> Sent from my iPad
> 
>> On 22 Sep 2020, at 9:41 am, Jonathan Yuen <jonathan.y...@slu.se> wrote:
>> 
>> Hi,
>> 
>> I have an FTDI converter, bought it to connect the M100 to modern stuff 
>> without real RS232 ports.  But I was trying to get ppp to work on the 
>> PI-Psion connection and I was trying everything possible (and it still 
>> doesn't work) under linux.  I can get it to work on Windows but that sort of 
>> defeats the whole purpose of having something small bridge between the Psion 
>> and today's internet.  I really only wanted to get mail to work so I didn't 
>> have to type on the phone or tablet screen but maybe a small bluetooth 
>> keyboard is the answer. If I keep the mail on the pi I guess I can use any 
>> terminal to do mail, like the M100 or the Psion but the M100 keyboard is 
>> better.
>> 
>> How to configure ppp to work is still a mystery but that is really not the 
>> subject of this list. Tried slirp and even found a number of people that 
>> claimed it would work but it doesn't work for me and it doesn't want to 
>> compile on my linux machine, either.
>> 
>> Jonathan
>> 
>> jonathan.y...@mykopat.slu.se
>> ________________________________________
>> Från: M100 [m100-boun...@lists.bitchin100.com] för Tom Wilson 
>> [wilso...@gmail.com]
>> Skickat: den 21 september 2020 22:06
>> Till: M100 Mailing List
>> Ämne: Re: [M100] definition of null modem
>> 
>> Some tips on that....
>> 
>> Are you using Linux on the Pi? If so,  it would be easier to just use a USB 
>> serial port. The Prolific and FTDI ports both work with Raspbian; I've used 
>> both.
>> 
>> Otherwise, maybe look at a DTE wired level converter with CTS/RTS.... like 
>> this one:
>> 
>> https://www.amazon.com/NulSom-Inc-Ultra-Compact-Converter/dp/B00OPU2QJ4/ref=sr_1_4?dchild=1&keywords=ttl+rs-232+level+converter&qid=1600718673&sr=8-4
>> 
>> Although I'm not sure where you'll get CTS and RTS on the Pi. I don't know 
>> that it's mapped to any of the GPIO pins. This might help a little bit:
>> https://www.raspberrypi.org/forums/viewtopic.php?t=241623
>> 
>> 
>> 
>> Tom Wilson
>> wilso...@gmail.com<mailto:wilso...@gmail.com>
>> (619)940-6311
>> K6ABZ
>> 
>> 
>> On Mon, Sep 21, 2020 at 12:10 PM Jonathan Yuen 
>> <jonathan.y...@slu.se<mailto:jonathan.y...@slu.se>> wrote:
>> Hello,
>> 
>> I actually am trying to connect a Psion 5MX with it's 'serial cable' to a 
>> raspberry pi, the serial lines on the GPIO thing.  The pi is TTL, so I have 
>> an adapter to change it to RS-232.  The adapter is DCE, but the Psion cable 
>> actually terminates as DCE, since it was made to plug into the serial port 
>> on your PC for synchronizing etc.  The Psion has a perfectly good comm 
>> program, so I'm using it as terminal (there is even a VT100 program) but I 
>> need the 'null modem' or crossover connector to connect it to the 
>> level-shifter.  Since they were both female, I actually did the test with 3 
>> pieces of maybe 14 or 16 gauge insulated wire, maybe 3 cm long, with their 
>> ends stripped and pushed into the right holes. But I thought I should have 
>> something a bit more 'robust' and maybe do the other lines as well.
>> 
>> I think Psion actually made a modem that connected to this cable, but that 
>> must have been DTE.......
>> 
>> I guess I always thought of the 'modem' in null-modem as 'modem=DCE' since 
>> I've always connected DTE things together. But I appreciate the feedback 
>> from the group.
>> 
>> Jonathan
>> 
>> jonathan.y...@mykopat.slu.se<mailto:jonathan.y...@mykopat.slu.se>
>> ________________________________________
>> Från: M100 
>> [m100-boun...@lists.bitchin100.com<mailto:m100-boun...@lists.bitchin100.com>]
>>  för Tom Wilson [wilso...@gmail.com<mailto:wilso...@gmail.com>]
>> Skickat: den 21 september 2020 20:18
>> Till: M100 Mailing List
>> Ämne: Re: [M100] definition of null modem
>> 
>> "Null" means "none" or "zero." So "null modem" means "no modem."
>> This term is an adjective and should be coupled with "cable", "adapter", or 
>> some other noun to be of any use.
>> 
>> I don't see a need to re-define the term, since "null modem cable" is well 
>> established, and we all know exactly what the term means.
>> 
>> Strangely, there are times you actually need a null modem cable to connect a 
>> computer to a modem. Most CP/M computers used dumb terminals, as did any 
>> mainframe and minicomputer (also called a mini mainframe.) Since those 
>> computers were designed to have DTE devices plugged directly in to their 
>> terminal ports, you might need a null modem cable to connect a modem to the 
>> mainframe... Of course, in that case, we'd just call those "modem cables" 
>> (or, more commonly, the 8-pin modular to DB25 adapter would be labeled 
>> "modem".) So in that instance, we literally used a null-modem cable to 
>> connect to a modem....
>> 
>> Sometimes I love the English language.
>> 
>> Tom Wilson
>> wilso...@gmail.com<mailto:wilso...@gmail.com><mailto:wilso...@gmail.com<mailto:wilso...@gmail.com>>
>> (619)940-6311
>> K6ABZ
>> 
>> 
>> On Mon, Sep 21, 2020 at 9:16 AM Lee Kelley 
>> <l...@3footed.com<mailto:l...@3footed.com><mailto:l...@3footed.com<mailto:l...@3footed.com>>>
>>  wrote:
>> I've always thought "null modem" was a misnomer. It probably should have 
>> been called a "non modem cable" or simply a cross over cable as mentioned 
>> above.
>> 
>>> On Mon, Sep 21, 2020, 11:06 RETRO Innovations 
>>> <go4re...@go4retro.com<mailto:go4re...@go4retro.com><mailto:go4re...@go4retro.com<mailto:go4re...@go4retro.com>>>
>>>  wrote:
>>>> On 9/21/2020 10:59 AM, Jonathan Yuen wrote:
>>> 
>>> That said, I could only think that the other wiring should be same as a 
>>> null modem, but I thought that I should air my thoughts to see what other 
>>> people think.
>> 
>> I'm curious about the use case, but you are correct, the wiring would be
>> the same.  Maybe, (though no one will do this, as the other terms have
>> been in use for too long), it's best to call such a cable a "crossover"
>> cable, like is available for Ethernet ports.
>> 
>> Jim
>> 
>> 
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