This is great but why cannot you do it? I think it is cheaper, no mechanics (that can fail), easier to build and only you have to disable it by software. Even if user pushes the button, nothing will...
Yes, that explains everything. Unfortunately, I can't use the HSERIN/HSEROUT ports available in the 18F4550 because they are already taken doing the hardware communication. Increasing the baud rate...
CircuitLab simulation
I just discovered this online tool.
Demon Today, 06:19https://www.circuitlab.com/
I just completed the first lesson as I was watching the video and I'm really impressed. So far it seems to be free.
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