Here’s a USB oscilloscope project from a few years back ... At the center, an ATtiny45 microcontroller uses its ADC capabilities for the two traces and also handles the USB connectivity.

For hackers on a tight budget or with limited bench space, a USB oscilloscope can be a compelling alternative to a dedicated piece of hardware. For plenty of hobbyists, it’s a perfectly valid ...

An oscilloscope makes the invisible world of electricity visible, letting you observe electrical signals on a video display in real-time. For $25, the Flea-Scope plugs into any computer via USB ...