# Regarding interfacing with GPIO pins

**URL:** <https://discuss.pynq.io/t/regarding-interfacing-with-gpio-pins/6539>\
**Category:** Support\
**Created:** [January 17, 2024, 3:24pm UTC](https://discuss.pynq.io/t/regarding-interfacing-with-gpio-pins/6539 "2024-01-17T15:24:03Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![Greek\_Sachdeva](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.pynq.io/greek_sachdeva/32/5531_2.png) [@Greek\_Sachdeva](https://discuss.pynq.io/u/Greek_Sachdeva)\
**Post date:** [January 17, 2024, 3:24pm UTC](https://discuss.pynq.io/t/regarding-interfacing-with-gpio-pins/6539/1 "2024-01-17T15:24:04Z")

</div>

Actually I have created a aes ecryption program and its bitstream and overlay is done from HLS and vivado.  
What I want is gpio pin to give high when my above program runs and gpio pin to give low when program ends.  
I have written in jupyter notebook the output gpio pin initialisation and high low code but when I try to measure it using an oscilloscope there is no deflection in oscilloscope.

Why the wire from GPIO pin 0 is not showing high low on probes from oscilloscope.

My final goal is to do power analysis of my aes implementation.  
so before doing that I was trying to see if basic high and low is detected in oscilloscope.

I am using pynq -Z2.