The device decides which mode to activate based on the mini-USB connection during boot (during power-up). If the device is connected via USB to a PC during boot, it activates MSD mode (or DFU mode if DFU switch activated) otherwise it activates Logging mode. If the device is in Logging mode and the USB is inserted at a later point, then the PC-interface is activated.
The selection of mode is illustrated in the figure below.
The LED interpretation depends on the mode of operation, for more information on LEDs see LED.
When the device boots with USB-port connected to a PC, it activates MSD mode. In this mode, the internal memory can be accessed via USB (similar to a USB memory stick). MSD mode allows the user to access logged data and the device configuration file.
Warning
To prevent corruption of the device file system, make sure to always safely eject the device from the PC.
When the device is powered on via the main (DB9) connector (without USB-cable connected), it activates Logging mode. In this mode, the internal memory is reserved for logging and cannot be accessed by the user. While entering Logging mode, the device reads the configuration (for more information see Configuration) file and applies the settings defined by the user.
Note
The device creates a default configuration file if the file is not found or not valid.
The serial interface can subsequently be activated by inserting the USB-cable. For more information see Interface.
When the device boots with USB-port connected to a PC while the DFU switch is activated, it activates DFU mode. DFU mode allows the user to update the firmware of the device.
The DFU switch is activated using a pointed non-conducting object
Sequence for entering DFU mode:
Make sure that device is powered completely off
Gently push and hold the DFU button, as illustrated in Figure 9
Connect the USB cable to power on the device
The device will power on and enter DFU mode (red LED constant on, green and yellow LEDs off)
Release the DFU button
Warning
Please make sure to use a non-conductive tool to activate the DFU switch
