Marine Instruments User Manual

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4.1 DATA COMMANDS
4.1.1 STANDARD DATA COMMANDS
bq27500
bq27501
System-Side Impedance Track™ Fuel Gauge
SLUS785 – SEPTEMBER 2007
The bq27500/1 uses a series of 2-byte standard commands to enable system reading and writing of
battery information. Each standard command has an associated command-code pair, as indicated in
Table 4-1 . Because each command consists of two bytes of data, two consecutive I
2
C transmissions must
be executed both to initiate the command function, and to read or write the corresponding two bytes of
data. Additional options for transferring data, such as spooling, are described in Section 7.1 I
2
C
INTERFACE. Standard commands are accessible in NORMAL operation. Read/Write permissions depend
on the active access mode, SEALED or UNSEALED (for details on the SEALED and UNSEALED states,
see Section 4.4 Access Modes).
Table 4-1. Standard Commands
COMMAND SEALED UNSEALED
NAME UNITS
CODE ACCESS ACCESS
Control( ) CNTL 0x00 / 0x01 N/A R/W R/W
AtRate( ) AR 0x02 / 0x03 mA R/W R/W
AtRateTimeToEmpty( ) ARTTE 0x04 / 0x05 Minutes R R
Temperature( ) TEMP 0x06 / 0x07 0.1 ° K R R
Voltage( ) VOLT 0x08 / 0x09 mV R R
Flags( ) FLAGS 0x0a / 0x0b N/A R R
NominalAvailableCapacity( ) NAC 0x0c / 0x0d mAh R R
FullAvailableCapacity( ) FAC 0x0e / 0x0f mAh R R
RemainingCapacity( ) RM 0x10 / 0x11 mAh R R
FullChargeCapacity( ) FCC 0x12 / 0x13 mAh R R
AverageCurrent( ) AI 0x14 / 0x15 mA R R
TimeToEmpty( ) TTE 0x16 / 0x17 Minutes R R
TimeToFull( ) TTF 0x18 / 0x19 Minutes R R
StandbyCurrent( ) SI 0x1a / 0x1b mA R R
StandbyTimeToEmpty( ) STTE 0x1c / 0x1d Minutes R R
MaxLoadCurrent( ) MLI 0x1e / 0x1f mA R R
MaxLoadTimeToEmpty( ) MLTTE 0x20 / 0x21 Minutes R R
AvailableEnergy( ) AE 0x22 / 0x23 10mWhr R R
AveragePower( ) AP 0x24 / 0x25 10mW R R
TimeToEmptyAtConstantPower( ) TTECP 0x26 / 0x27 Minutes R R
Reserved RSVD 0x28 / 0x29 N/A R R
CycleCount( ) CC 0x2a / 0x2b Counts R R
StateOfCharge( ) SOC 0x2c / 0x2d % R R
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