Question regarding proper cable to control Rossini Clock via RS232 cable

I just bought a new Rossini DAC + Rossini Clock. I also have a RS232 DB9 Serial “Null” 9 pin female to female 1 meter cable to attach from my Rossini DAC to the Rossini Clock to control standby of both products using the DCS Mosaic App on my iPad to set both in and out of standby via my iPad. Is the “Null” the appropriate RS232 cable for this purpose or the “standard.” RS232 cable?

Forgive me if this is a double post, but since I am new to the DCS forum, I apparently was unsuccessful in posting this question, so please bare with me. That would be most appreciated.
Thank you. Bob

Hi Bob,

You’ll need to use a straight-through RS232 cable for this, not a null modem / crossover cable like you currently have.

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I see from the attached thread linked that a “Null” type is not correct (assuming that the information is right) . The the thread also links to an actual product so I hope this is useful.

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A so-called straight RS-232 serial cable is a cable that connects identical pin numbers in each connector.

With a null modem RS-232 serial cable the transmit and receive lines, and sometimes also one or more handshake lines, are crosslinked.

From the dCS manual:

RTFM :wink:

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Yes, I believe the term “null modem” comes from traditional telecoms days when 2 “data terminal equipment” devices needed to be connected directly together, instead of over a telecoms circuit with modems either end. The circuit with modems either end performed the crossover that Ermos describes, so when removed the null modem cable performs that role.

Finally, I feel I can contribute something…!

Cheers, Mike.

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I made that error and accidently bought a Null version to start wtih.

I ended up buying this one: DTECH 5ft Serial Cable Female to Female 9 Pin DB9 Port:

I was after a much shorter one, but that was proving to difficult to source.

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:+1: That is the right one.

It says:

5 feet RS232 serial cable f-f adapter for some old RS232C equipment like scanner, Modem, printer, plotter, switches, camera, barcode / embroidery machine, touchscreen, microcontroller, test equipment

… and dCS gear of course :grinning:

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A big thank you to all who replied with helpful information to my “Null” RS232 cable question. I blindly ordered the “Null” cable as it was the only one that I could find which came in a sensible length of 1 meter. I should have checked with you guys first before ordering on Amazon USA, but at least I’m only out $5. I’ll look for a short “Standard” cable, but I wonder if it’s even worth it at this point??

In another thread, I decided to leave both my Rossini DAC and Rossini clock powered on 24/7 and I see no harm in doing so.

Thanks for the link. I just ordered the same cable from Amazon USA.