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Way to connect 50g to 48? - Printable Version

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Way to connect 50g to 48? - HP67 - 05-09-2014 03:12 PM

The IR connection isn't compatible between these two devices. Is there a standard cable that will work between a 50g and a 48?

Has anybody looked into what would be required to get a 50g and a 48 to talk over IR?

RE: Way to connect 50g to 48? - Egan Ford - 05-09-2014 05:25 PM

Serial.

RE: Way to connect 50g to 48? - walter b - 05-09-2014 05:29 PM

(05-09-2014 05:25 PM)Egan Ford Wrote:  Serial.

Serially. SCNR Wink

RE: Way to connect 50g to 48? - Marcus von Cube - 05-10-2014 06:43 PM

It's serial but it's not a straight connection but needs a level shifter instead. I found two articles that describe the port and a cable for both devices:

HP 48G: http://www.hpcalc.org/hp48/docs/faq/48faq-12.html
HP 50G: http://www.allenwan.com/hpcalcserialcable/

Some soldering required...

RE: Way to connect 50g to 48? - Michael Lopez - 05-11-2014 01:49 AM

Alternatively, you can buy a suitable pre-made serial cable from Eric at hpcalc.org (see http://commerce.hpcalc.org/ ). This is what I did & it works fine.

Cheers,

Michael

RE: Way to connect 50g to 48? - HP67 - 05-11-2014 05:51 AM

Thanks for the links, Marcus. Bookmarked!

Michael, I see a serial cable for the 50g on hpcalc but I don't see a cable that would work between a 50g and a 48. Did I miss something, or did you mean if I get the 50g cable it will work with a stock 48 cable? Thanks.

What about IR between the 50g and the 48? Has anybody looked into it? (no pun intended).

RE: Way to connect 50g to 48? - Michael Lopez - 05-11-2014 09:32 AM

Hi HP67,

The cable you need to purchase is the one called: "HP 50g RS-232 Serial Cable". Then you plug the old standard HP48 serial cable (HP type or other) into the 9 pin D-Plug end of this new cable resulting in suitable connections at both ends for the HP50G & HP48 series calculators.

Just be aware also that the transfer must be performed in ASCII Kermit mode & it is only safe to transfer standard User RPL programmes & functions. If you try to transfer System RPL programmes & functions you will crash one or both calculators due to the differences in internal addressing etc.

Cheers,

Michael

RE: Way to connect 50g to 48? - HP67 - 05-11-2014 09:39 AM

Thank you, I will get one of those. Sounds very convenient!

RE: Way to connect 50g to 48? - Marcus von Cube - 05-11-2014 10:11 AM

(05-11-2014 09:32 AM)Michael Lopez Wrote:  The cable you need to purchase is the one called: "HP 50g RS-232 Serial Cable". Then you plug the old standard HP48 serial cable (HP type or other) into the 9 pin D-Plug end of this new cable resulting in suitable connections at both ends for the HP50G & HP48 series calculators.
Are you sure you can just plug them together? If both are targeted at a PC com port you'll need a null modem with two 9 pin male connectors as an adapter.

EDIT: I stand corrected! Here is the description of Eric's cable:
Quote:Our cable has a standard male 9-pin connector for connecting directly to serial devices with no gender changer needed. While it is possible to connect it to a computer by using a null modem adapter, we feel that most users would prefer to use a USB cable for a PC link, allowing us to not need an adapter when connecting to serial devices.
So no null modem required.

RE: Way to connect 50g to 48? - HP67 - 05-11-2014 10:17 AM

The 50g cable at the HPCalc site seems to have the right gender to match the standard 48 cable.

Part of the info there says "Our cable has a standard male 9-pin connector for connecting directly to serial devices with no gender changer needed. While it is possible to connect it to a computer by using a null modem adapter, we feel that most users would prefer to use a USB cable for a PC link, allowing us to not need an adapter when connecting to serial devices."

http://commerce.hpcalc.org/serialcable.php

This looks ok, but I really don't know.

RE: Way to connect 50g to 48? - Michael Lopez - 05-11-2014 12:29 PM

Hi all,

I've been using Eric's cable for a couple of years & can confirm the standard HP48 cable plugs straight in without using a null modem or any other device. If I get a chance this week, I'll post a photo showing how they fit together without modifications of any kind.

Once the cables are connected together & you set-up the communication on both calculators to serial etc, it works flawlessly.

Cheers,

Michael

RE: Way to connect 50g to 48? - HP67 - 05-11-2014 12:48 PM

Thanks again. This looks like a great suggestion and a great product.