Keyboard Latency Tester

Hello there, I recently bought an Arduino Due and my new keyboard arrives. I want to test the input latency from it, but the example code does not help me too much and I am stuck. I want to measure the input latency of a single key on the keyboard at least for now and record it in milliseconds. I intend to probably press a key 5 times to get a good sample to average out the data. I will do this for all the keys to see if there are any variances. The point of all of this is to create a timeline of latency for my new keyboard across firmware versions.

Just to provide a little more information, I can definitely read and see what keys are getting pressed. My issue is pulling the input timings from the keyboard, not the time in between presses.

Do you have a physical and logical interface describtion about the keys?

I am not sure exactly sure what you mean, by physical and logical interface. The keys use hall effect technology and the keyboard determines which one(s) are pressed by multiplexors. There are 4 debug holes, but there is no documentation hence why I want to determine input latency via the universal serial bus port.

physical and logical interface characteristics.
Voltage level and timing etc…

Please post a code snippet that reads the keyboard output.

I only know of keyboards that send make and break messages, not raw key messages.

Something interesting project. Can you share the details of your proceedings to implement it