one of the very old tricks, that’s even documented is how to simulate ctrl-break on newer PCs to break into ROMMON during router/switch boot.
instead of fighting with SecureCRT on MacOS, I just used it recently.
- disconnect terminal from the device
- turn device off
- set terminal to 1200 (yes, you read this right), 8N1 and no flow control
- turn device on
- press SPACE for 10-15 seconds (basically, until your terminal drops out some unreadable characters)
- reconfig terminal to 9600 8N1 and you should be in ROMMON
yes, I’m old.