IBM 7013 J Series Operator's Manual page 37

Using the Reset/Scroll Button
Attention: When the mode switch is in Normal or Service position, pressing the
Reset/Scroll button causes the unit to reset and do an IPL (Initial Program Load). Pressing
the Reset/Scroll button while the operating system is running can result in damaged or lost
data.
The Reset/Scroll button is used to:
Reset the system unit and cause a boot when the mode switch is set to Normal or
Service. Pushing the Reset button once may cause an incomplete reset and the system
may not restart. Therefore it is recommended to push the reset button twice for a
complete reset.
Read out messages (scroll) after a flashing 888 is displayed.
Start the dump program when a manual dump is needed.
Sequentially read system configuration in Stand-By Mode and with the key mode switch
in Service position.
Pushing the Reset button once causes an incomplete reset and the system may not restart.
Therefore it is recommended that you push it twice for a complete reset.
When the mode switch is in the Secure position, the Reset/Scroll button is disabled.
Reset/Scroll Button
2-5
Using the System Unit