Adam Taylor MicroZed Chronicles: Issue 106 Interrupt Latency Part 2

Continuing with Adam Taylor's tutorials in his MicroZed Chronicles on the XADC. This post relates to issue 106, which can be found using the link at the bottom of the page.

What I learned from Adam's Tutorial:
This tutorial is a continuation of issue 105.

Here, the interrupt latency we will be measuring is the time required to start executing the ISR.

We left off in Vivado having just created the Bitstream. Now we are ready to move into SDK.
Export Hardware > Check Include Bitstream > Launch SDK

Once in SDK:
File > New > Board Support Package > Finish
File > New > Application Project > Hello World > Finish

Copy and paste in the .C file from Adam Taylor's github (https://github.com/ATaylorCEngFIET/MicroZed-Chronicles) and replace it with helloworld.c and SAVE IT.

Next launch minicom > Program FPGA > Run

You should see something similar to this within minicom:
 
This is reading the value on the AXI Timer as soon as the ISR is called. Our interrupt latency is about 410 nsec. 

Next, we will see how this can be combined with the XADC to receive an analog signal!

http://zedboard.org/content/microzed-chronicles



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