Break key for solaris sparc with serial terminal

Question

On Solaris I use stop+a to enter prom If terminal is serial console without stop key,what is the break key? I try

stty -a 

but no break key found.

CTRL+C of course doesn't work because only interrupt program

Answer 1

A serial BREAK is essentially caused by the sending device holding the Tx line low (0V) for a period of time. It's not a character.

On a real terminal (eg a VT100) there was a key marked BREAK in order to do just that.

With terminal emulators and software it depends very much on the program you are using. tip, for example, can send a BREAK with ~#. With C-Kermit you would press Control+\ followed by B.

Now there is a problem with BREAK... if the terminal was power cycled it sometimes caused the Sun machine to think a BREAK was being sent and would drop the machine into PROM mode. Not good. So an alternate key sequence was made possible.

kbd -a alternate

Which may also be set as a default in the /etc/default/kbd file.

With alternate mode enabled the serial driver will treat the sequence

RETURN ~ Control+B

as a BREAK.

(That's "RETURN" then "~" then "Control+B")