2.5
Status Indicators
System status is indicated by the two LEDs located near the USB connector. The blue LED indicates
system operation and blinks once per second to indicate a properly operating system. The blue LED
blinks when the X16-5 is recording data, in standby mode, or is connected to a computer via the USB
port. The red LED blinks when data is written or read from the microSD memory card. In data
logging mode, the period at which the red LED blinks depends on the sample rate and other
configuration settings. The LEDs will flicker during user initiated shutdown. The “statusindicators”
tag in the configuration file turns off or changes the brightness of the status indicators (see section
2.6.13). The red charge indicator LED is located on the reverse side of the circuit board and
illuminates when charging is in process (see Figure 12). The charge indicator LED will turn off when
the battery is fully charged. A fully discharged battery will charge in about 2 hours. A blinking charge
indicator LED means there is a problem with the lithium-polymer battery pack.
Gulf Coast Data Concepts
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X16-5, Rev New
Initializing the RTC ensures that the start time and individual time stamps can be
correlated to an absolute time – the year, month, day, hour, minute, second, and fractional
second. An uninitialized RTC or reset of the RTC will lead to indeterminate start time
recorded in the data file header.
After unplugging the logger from the USB port, the logger will load the config.txt file and
time.txt file, if present. Therefore, there is a delay between when the time.txt was created
and when the logger actually loads the time information. For most applications, this simple
method of initializing the clock results in sufficient accuracy.
Figure 11: Example Time Entry in time.txt File
