Max frequency of input pulses for LPC1547

Discussion created by lpcware Employee on Jun 15, 2016
Latest reply on Jun 15, 2016 by lpcware
Content originally posted in LPCWare by iharihar on Fri Feb 12 07:35:31 MST 2016
Hello, everyone.

I want to create a counter of high frequency pulses using 
an external special counter chip and LPC1547 SCTimer ( in counter mode) connected consecutively.

What max frequency of the pulses (duty cycle 50%)  can I count reliably?
My LPC1547 board has 12Mhz ext osc and 72Mhz  system clock.

Can I use QEI module in clock/direction mode for this goal?
What is max freq of input signal for QEI module?
I did't find anything in LPC15xx data sheet and manual  concerning my question.
Will  NXP support team be able to answer me?