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Nullmodem Cable RS422 to RS232 ...
- Thread starter franklyn
- Start date
You may also want to have a look at the web page
http://www.knubbelmac.de/wie-geht/datenaustausch/datenaustausch-nullmodemkabel.html
It has an outdated link to a "Nullmodemkabel" (you could try the Wayback Machine), but for DB-25 on the PC side. If necessary, adapters DB-25 to DB-9 are available.
Alternatively, you should be able to use a normal MiniDIN-8M to DB-25M Mac modem cable combined with a standard DB-25F-to-DB-9F PC-style null-modem cable. As always, double-check the pinouts before connecting anything.
Mk.558
Well-known member
Alas, they are but gone.
Those Mini-DIN-8 RS422 to DE-9 RS232 adapters from Palm are gone. I got two off Amazon roughly 12 years ago. Can't find any more on ebay. Ugh anyways if you're looking for a generic RS232 adapter, the 3rd one from the bottom of the image on dochilli's post is how the palmOne adapter is wired up, and should work fine. From there, you can get a null modem adapter (they make null modem adapters that look like gender changers), then a regular DE-9 conventional straight cable and roll out.
Those Mini-DIN-8 RS422 to DE-9 RS232 adapters from Palm are gone. I got two off Amazon roughly 12 years ago. Can't find any more on ebay. Ugh anyways if you're looking for a generic RS232 adapter, the 3rd one from the bottom of the image on dochilli's post is how the palmOne adapter is wired up, and should work fine. From there, you can get a null modem adapter (they make null modem adapters that look like gender changers), then a regular DE-9 conventional straight cable and roll out.
ADTPro provides the following pin out: https://adtpro.com/connectionsserial.html. This is a hardware handshaking null modem (TX/RX lines swapped) cable that can be plugged directly into a USB to DB-9 RS-232 serial adapter. The biggest problem I've encountered over the years by far is getting a modem working above 9600bps due to incorrectly MiniDIN-8 to DB-25 modem cables that did not correctly support hardware handshaking.
Mk.558
Well-known member
That's an interesting arrangement. I'll probably reference that when I update that image soon.
E: note that the image above for ADTPro is a crossover cable, which arguably the better choice is to make it a straight cable and then use a null-modem adapter thingy so you can use it for "other things" besides direct computer-computer connections.
E: note that the image above for ADTPro is a crossover cable, which arguably the better choice is to make it a straight cable and then use a null-modem adapter thingy so you can use it for "other things" besides direct computer-computer connections.
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