When you say measure signals, that's a very loose term. Are you measuring a pulse width, continuous wave frequency, etc, what sort of accuracy and resolution do you require, etc. At low speeds you would normally use interrupts to start a counter and count clock ticks for example.There is always some uncertainty associated with this since the resolution will be associated with the cycle time of the processor. You may need to go to a high speed external counter, with a bit of logic, and use that to interrupt the processor, which would then interrogate the counter using an SPI interface, for example. This could be implemented in a high speed FPGA . Without a few more details about the wave forms, how they vary, and what it is you need to measure I would hesitate to offer any further comment,cheers,Richard
