[londons_explore]

Not OP, but for USB "full speed" devices (12 Mbps), you can use a saleae logic analyzer clone ($12) with the opensource pulseview which can decode USB frames and streams rather well.

Even with faster devices, you can usually force them down to 12 Mbps with a USB 1.1 hub for analysis and bugfixing of the driver/firmware, and then have the exact same code work fast without the hub.

On desktop, wireshark also has the ability to monitor USB data transfers for a software-only approach.

[tonetegeatinst]

I got a cheap logic analyzer that does 8 channels.

My main concern is needing more than 8 channels or a higher sample rate.....and those are so expensive.

Its also hard to tell who is telling the truth on spec sheets.