I'm building my own CNC milling machine and one of the safety features that they advise you to build is a frequency safety switch (aka charge pump) that activates a relay when there is a constant 8-13KHz signal from the computer.
I would like to build mine using a pic like the 12C508/P, which I have plenty of spare and eager to make use of/get rid of...
So the circuit is essential one input pin (for the signal 0-5V) and one output pin for the relay)
I realise that the 555 timers are able to do a similar thing already with 'missing pulse detectors' but i'd like to have the advantage of fine tuning the algorithm to cater for checking the pulse width, etc in the future.
I'm just struggling to get my head round the code as usual...
Any ideas or code examples I could use to get started?
thanks!
I would like to build mine using a pic like the 12C508/P, which I have plenty of spare and eager to make use of/get rid of...
So the circuit is essential one input pin (for the signal 0-5V) and one output pin for the relay)
I realise that the 555 timers are able to do a similar thing already with 'missing pulse detectors' but i'd like to have the advantage of fine tuning the algorithm to cater for checking the pulse width, etc in the future.
I'm just struggling to get my head round the code as usual...
Any ideas or code examples I could use to get started?
thanks!