Max frequency of input pulses for LPC1547

[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?

[lpcware]

Content originally posted in LPCWare by IanB on Fri Feb 12 09:12:41 MST 2016
For the SCT, maximum is half the system clock frequency - see the description of the SCT configuration register. (Table 202 in the LPC1517 manual)