Anybody know how to "break" a long-running command (e.g. ping with high repeat count) on Cisco Small Business switches?

Title says most of it...

I have a bunch of Cisco SG300, SG500, and SG350X all over the place. I know that on "real" Ciscos, Ctrl + Shift + 6 is usually the break sequence, e.g. to terminate a long-running ping command.

Ctrl+shift+6 does nothing on the Small Business series CLIs.

I've also tried:

• ctrl + break
• shift + break
• ctrl + shift + break
• ctrl + alt + shift + break
• sending "break" from the telnet client itself (and before anyone starts with "reeee telnet isn't secure," I'm fully aware, and I only use telnet if I know the network itself is secure e.g. I'm plugged straight into the switch with nothing else between. The way these switches handle SSH sucks [they ignore whatever username you send over SSH and make you manually input it again], so telnet is mildly more convenient.)

Anybody have a clue?