FE310 RTC Change Frequency

Is there anyway to get the frequency for the RTC to be any higher? I need more precision out of it in order to send 10 uS pulses to a ultrasonic sensor and the current RTC resolution is not high enough. I have already set the scaling register to maximize the resolution but a Frequency of ~32 kHz is too low. Any suggestions?

I don’t think so, unless you want to cut a trace and try configuring the onchip lfclk to go higher (but afaik that’s only for testing and not a stable clock, and doesn’t go much higher anyways).

Have you looked into PWM? I think that is driven by the tileclock (aka the baseclock on the FE310), so should be at least 16MHz. I haven’t tried this but there is a way to chain the comparators together which might let you create an envelope pulse.

Further, there is a way for the PWM to trigger interrupts if the chain behavior isn’t versatile enough.