Simple potentiometer

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Beg_inner

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Hello world,
I'm totally new on this forum and with arduino/teensy
I'm playing with teensy and try to connect a simple pot. On arduino it's OK: pot one side value 0 and 0Volt other side value 1023 and 5Volt... But on teensy the 5Volt is here on the middle of the pot! So the entire pot is not used only half the pot. It's a 10cm pot 10k linear, tried with a 50k pot also and same résults. So why teensy don't use the entire pot?
 
Unfortunately, you did not write which Teensy you are using. It's difficult to help when the most important informations are missing.

In case you use a modern 32bit Teensy (LC or 3.x), a short look onto the data sheet would tell you that, depending on the setting of the analog reference voltage, the ADC full scale is either obtained at 3.3V (default) or at 1.2V (with alternate reference settings). When using such a modern Teensy, it is recommended to connect the potentiometer between 3.3V and GND, and it it is strictly forbidden to apply more than 3.3V to the analog input pins because that would kill the internal ADC.

In case you use the old, slow, and outdated 8bit Teensy 2.x, things are different.
 
Electronic circuit design requires meticulous study of the components' data sheets BEFORE a single physical connection is made...
 
The Teensy 3.2 - Most of the IO pins are +5v tolerant, except for a few analog only pins which are only 3.3v.

On the Teensy 3.2, the analog system works with up to 3.3v. The hardware can handle the 3.3v, but anything over that will read as 1023 (or the maximum for the current set analogResolution....

So if you wish for full range, connect the pot to 3.3v instead of 5v. Or setup the output through a voltage divider to cut down the voltage, or...
 
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