setInterval hanging and USB connection on Pico?

Thanks! Your stopgap seems to be solving my problem. I can definitely wait a few seconds after boot before starting the loop. I can't use the setDeepSleep because I'm using a Serial port for radio. I'm considering switching to the analogWrite strategy that you suggest as well because I do need to pulse a pin in my actual project. Pulling a pin down is what triggers a read on a Lidar unit. Anyhow, I think I'm back in business. I know it isn't an energy efficient solution, but my unit will be plugged into wall power, so energy efficiency isn't my main concern. Thanks again.