Awhile ago I had purchased a 2.5mm to 3.5mm adapter to so that I could listen to audio. Unfortunately I made what I thought was an oversight but actually it ended up not being an issue.
Casio and I think TI calculators use a 2.5mm TRS connector for the serial port. This means tip, ring and sleeve. Many smartphones and other small devices use a TRRS connector so that way it's possible to plugin in a headset that has both a microphone and stereo speakers.
What I figured out at-least in my case it just so happens that the tip and the first ring are the same size and in the same position so when I plug in my adapter what happens is the extra ring and the sleeve become short circuited which is fine because it just ends up acting like the longer sleeve found on a TRS connector. TX and RX don't get short circuited so it ends up working out.
The implications of this are that you might be able to safely use the adapter you might use for your smartphone or other device on your calculator even though its a TRRS adapter instead of a TRS adapter. Now of course this information is provided without any warranty and I strongly suggest you check it with a multi-meter and make sure the tip and first ring line up and that the extra ring(s) are only taking up the space where the sleeve would have gone.
Now of course you can just purchase a TRS adapter and avoid having to worry about this. That is probably your safest option.
I'm using it on my calculator right now and it's working great.
I thought I would also ask if there are any adapters that are dangerous for a calculator so people know what to purchase if they are interested in buying an adapter.
Casio and I think TI calculators use a 2.5mm TRS connector for the serial port. This means tip, ring and sleeve. Many smartphones and other small devices use a TRRS connector so that way it's possible to plugin in a headset that has both a microphone and stereo speakers.
What I figured out at-least in my case it just so happens that the tip and the first ring are the same size and in the same position so when I plug in my adapter what happens is the extra ring and the sleeve become short circuited which is fine because it just ends up acting like the longer sleeve found on a TRS connector. TX and RX don't get short circuited so it ends up working out.
The implications of this are that you might be able to safely use the adapter you might use for your smartphone or other device on your calculator even though its a TRRS adapter instead of a TRS adapter. Now of course this information is provided without any warranty and I strongly suggest you check it with a multi-meter and make sure the tip and first ring line up and that the extra ring(s) are only taking up the space where the sleeve would have gone.
Now of course you can just purchase a TRS adapter and avoid having to worry about this. That is probably your safest option.
I'm using it on my calculator right now and it's working great.
I thought I would also ask if there are any adapters that are dangerous for a calculator so people know what to purchase if they are interested in buying an adapter.