How can we count frequency of an input with the BL2600. And which input can do it. And what is the maximum frequency measurable.
Is there any program example
Use the input capture function of Timer A. The preferred pins would be DIN21 or DIN23, which are connected to CPU ports PF5 and PF7 respectively. Both of these pins can be used for input capture functionality. It is also recommended you remove any jumpers from JP4 (no pullup or pulldowns on DIN21 thru DIN23) to minimize filter affects on the lines. Please refer to section 7.13 of the Rabbit 3000 Microprocessor User’s Manual for more information on using input capture. A link to the download page for the user manual and the board schematic is below. Also look at the sample program IC_TEST.C in the SAMPLES/Rabbit3000 directory.
Get the CPU User’s Manual & board schematic here:
[BL2600 Documentation](http://www.rabbit.com/products/bl2600/docs.shtml)