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Full Version: Serial Ports - HP48, PC, HP200LX, etc
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Being frustrated with various device pinouts, I've 'published' a diagram (it's an Excel Book) of various Serial port pinouts here:

http://tchrapkiewicz.googlepages.com/hp48

[Serial Ports Link]

I can add the HP49 pinout once I find one.

Also, the pic at the top of the page is an overlay (still working on getting the layers lined up) of both sides of an HP48 PCB.

TomCee

A quick look at 2 versions of the HP48 connector has me wondering.
On the RS232 sheet, the pinouts are in the sequence STRG.
On the HP48 sheet, the pinouts are in the sequence GTRS.

Ken:

I'm glad that you brought this up - as this is EXACTLY the reason why I put this information on this sheet in the format that it is.

The descriptions I put on the connectors refer to the data direction at the device itself. The diagram you are referring to on the HP48 page has the nomenclature referring to the PC that the HP48 is connected to! Notice the direction of the arrows on the diagram, and you can clearly see that the 'T' line of the calculator is going to the RX line of the PC. etc...

Regards,
TomCee

Thanks for the explanation.

I've updated the sheet to include the HP49 connector.
TomCee