PNI SENtral - Manual (Page 26)

PNI Sensor Corporation Doc #1018049 R03
SENtral Technical Data Sheet Page 25
5.4 Standby State
In Standby State overall system power consumption is dramatically reduced because both the
SENtral algorithm and the sensors are shut down. Table 5-7 provides the registers associated
with Standby State.
Table 5-7: Standby Registers
Register Name Address Register Value
AlgorithmControl 0x54
[0] 1 = StandbyEnable
0 = Disable Standby State
AlgorithmStatus 0x38
[0] 1 = SENtral in Standby State
0 = SENtral not in Standby State
The steps to enter and exit Standby State are given below:

Write 0x01 to the AlgorithmControl register. This places SENtral in Standby State.

Read the AlgorithmStatus register. If bit [0] is ‘1’, then SENtral is in Standby State.
This step is optional.

When you are ready to exit Standby State, write 0x00 to the AlgorithmControl
register. This takes SENtral out of Standby State and normally will place it back into
Normal Operation.

Read the AlgorithmStatus register. If bit [0] is ‘0’, then SENtral is not in Standby
State. This step is optional.
5.5 Pass-Through State
SENtral can be configured so the host communicates directly with devices on the sensor bus
by placing SENtral into Pass-Through State. In Pass-Through State, SENtral’s sensor and
host interfaces are connected by internal switches so the host system communicates directly
with the sensors and/or dedicated EEPROM. To enter Pass-Through State, SENtral first
should be in either Standby, Initialized, or Unprogrammed State. Consequently, in Pass-
Through State the SENtral algorithm, host interrupt line, and sensors are disabled, unless a
sensor is directly turned on by the host. When exiting Pass-Through State, SENtral will
return to its prior state.
Note: When entering Pass-Through State the sensor’s registers retain the values established by
SENtral, and when exiting Pass-Through State any register changes will be retained.