IBM 7015-R30, Installation And Service Manual

Page: 289 / 300

System Power States
E-1
Appendix E. System Power States
The state of the system is dependant on the condition of four variable conditions that effect
how the system IPLs or shuts down. The four conditions are:
•
the position of the Power-on button
This button has two positions. It can be pressed in to the On position (position for turning
the power on), or it can be in the out or Off position.
•
the position of the system key (physical key mode or electronic key mode)
The system key represents the condition (Normal, Secure, or Service) that the system is
set to by the physical key mode switch or the electronic key mode switch.
•
the
was_shutdown
status
The system keeps a record when it has been shutdown using the shutdown –F
command since the last IPL.
•
the
power_fault
status
The system keeps a record when it receives a power fault condition since the last IPL.
Power States
The state of the system depends on how the variables were set either when the power was
applied to the system, or when the power was removed.
MAIN_STANDBY
This is the initial state of the system when power is first applied (by plugging a 7012 G
Series into an electrical outlet, or by setting the main power switch of the 7013 J Series to
the On position for example). When in this state, the BUMP console displays
STANDBY,
unless the console is set to display the operator panel display error messages.
The Power-on button and the BUMP console Enter key are polled by the system
continuously for a change in status. The system remains in this state until one of the
following occurs:
•
If the Power-on button is initially detected to be in the On position, and the
was_shutdown
status is false, the system goes to the WAIT_POWER_ON state.
•
If the Power-on button is pressed and changes from the Off position to the On position,
the system goes to the WAIT_POWER_ON state.
•
If the Power-on button is pressed and changes from the On position to the Off position,
the system sets the
was_shutdown
status to false.
•
If the BUMP console Enter button is pressed, the system goes to the SBB_GATEWAY
state.
SBB_GATEWAY
In this state the > character is displayed on the BUMP console and the cursor is located two
spaces to the right of the > prompt (> _).
•
If the command
sbb
is entered on the BUMP console, and the system key is in the
Service position, the system goes to the SBB_MENU state.