IBM 5150

Below are a few examples of "CONTROL" functions:
"CTRL + NUM LOCK" = SUSPEND
Suspends system operation so
you can read the display.
Press any key
to continue.
"CTRL + PRTSC = ECHO
Echos and prints
what you type and what the system
displays until
you press these keys again.
"CTRL + SCR LOCK/BREAK" = BREAK
This stops
your command program while it's running.
Keyboard 3-10