Pulse Counter on G120

I wanted to use this idea on the G120 module to make a RPM display
https://www.ghielectronics.com/docs/108/register-access

I will look up the LPC1788 register set.

But I want to know which counters are free to use; meaning GHI is not using, so it does not mess up something else.

If any one has some code snippet where they use the counter on G120, please share and thanks in advance.

You can use signalcapture to measure the time between pulses and thus derive RPM.https://www.ghielectronics.com/community/codeshare/entry/928

take a look at this code
https://www.ghielectronics.com/community/codeshare/entry/753

Very nice.

Thanks hagster & MikeCormier