The DS1101 can be powered through its power jack, pin 9 of the DB9 (RS232) connector, or the optional PoE module (letter " P" in the model numbering scheme).
Pin 9 input has the same input voltage requirements as for the power jack.
Optional PoE module is supposed to be powered by 48V (nominal), which is standard for PoE equipment. Your PoE-enabled hub will take care of this. The PoE module outputs 12VDC.
Internally, all three power sources are connected to the DS1101's power regulator through three diodes, as shown on the diagram below.
Pin 9 of the DB9M connector can also be used to provide "12VDC" power to an attached serial device. Many small serial devices, such as barcode scanners, accept power on pin 9 of their DB9 connectors.
We intentionally printed "12VDC" in quotation marks. This is because there is no guarantee that the output voltage will be exactly 12V. It will actually be the "input voltage minus the voltage drop across the diode". In plain words, it will be slightly below the input voltage. If you connect 12V to the power jack you will get around 11.7V out of pin 9.
To turn the power switch on from within your Tibbo BASIC/C application, enable (configure as output) the PL_IO_NUM8_PWROUT GPIO line and then set this line to LOW. Additional programming information can be found in TIDE, TiOS, Tibbo BASIC, and Tibbo C Manual (see i.o object and the DS1101 platform documentation).
Note that the DS110x devices cannot accommodate the PoE and Wi-Fi options at the same time.