I'm writing a SPI Master module for my FPGA and I would like test it with my Arduino Uno. What's the problem? My FPGA has 3.3V logic and Arduino has 5V TTL logic. So, what's the simplest solution to convert 5V TTL logic into 3.3V logic?
I know this topic has been already discussed in many sites but I can't find an unified answer.
Thanks in advance!