I need to design a frequency counter that will measure frequency inputs between 10Hz and 50KHz using a Philips 89C664 and the C Language. I have looked through this message forum and have found a lot of good advice and starting ideas, but maybe someone out there has more specific info. The microcontroller that I am using executes one machine cycle in 6 clock cycles rather than the standard 12. My external oscillator is 10 MHz. I need to measure the frequency and then display it on my VFD. I already wrote the code to display characters on the VFD, now all I need is the frequency value so I can display the measurement. I am used to writing my codes in C rather than Assembly. Any help would be greatly appreciated, especially with figuring out the timing part based on my external oscillator and the chip I am using. I am familiar with the set up of timers and counters I just need help writing a stable algorithm using both the Timers and Counters to measure the frequency.

Thanks,
Sarah