System Management Output Port (J1)
The four 2-pin ports at J1 provide an alternative way for peripherals to
enter into System Management mode. Plug the connecting cables from
peripherals capable of power management mode into any pair of the four
J1 SMOUT ports (SM0, SM1, SM2, and SM3).
1
2
SM0
High: Normal mode
Low: Doze, Standby, or Suspend Mode
(pin 1: control pin; pin 2: ground pin
SM1
SM2
SM3
The System Management Output is an active low signal. When the board
enters any power management mode, the SMOUT will sense it and
change the signal from high to low. Accordingly, peripherals attached to
the SMOUT ports will shut down and will not restart until the board
returns to Normal (high) mode.
Power Management (Green) LED (D4)
The Green LED connected to D4 indicates the power management state
of the system board. When in normal mode, the output will be low to
indicate the Normal mode. When timed out, the output will switch high
to indicate the Doze, Standby or Suspend mode.
2-10
Manual No. 771924-D03, Mar. 1995
MGI486 System Board User's Guide
