The Intel® Edison kit for Arduino allows the Intel® Edison to be compatible with Arduino shields designed for the UNO R3. The Arduino Expansion Board includes several jumper headers to configure the board with different settings like IO voltage levels, ADC voltage reference, PWM pins selected, power supply battery connection, etc.
For more details, please visit https://communities.intel.com/docs/DOC-23455
Step 1: About the Jumpers
1. IOREF (J9): The IOREF header allows selecting between two voltage levels: 5V or 3.3V, to make the IO pins compatible with the level selected. The selection is made through a jumper. The default IOREF value selected is 5V as showed in the picture above.
2. AREF (J8): The AREF header allows selecting the ADC voltage reference. The reference can be selected between the IOREF value and an external value on the AREF pin. The selection is made through a jumper. When the IOREF value is selected, it can be 3.3V or 5V depending on the IOREF jumper position. When the AREF value is selected, it can be chosen from a voltage range from 0V to 2.5V if the IOREF is 3.3V or from 0V to 5V if the IOREF is 5V. The default ADC voltage reference selected is the IOREF value as showed in the picture above.
3. NTC (J13): The NTC header allows setting an NTC thermistor input used to monitor battery temperature while charging. This feature can be disabled connecting the NTC pin to GND which is the default position of the NTC jumper as showed in the picture above. To enable this feature tie a 10K thermistor from the NTC pin to GND. The jumper is no needed to enable this feature.
4. ICSP (J4): The ICSP header has the same functionality as the ICSP header found it in the Arduino UNO boards.
5. BATT (J2): The BATT header allows attaching a Li-Ion battery for those low power applications. Make sure the battery is attached with the correct polarity.
6. PWM (J11-J12): The PWM headers, also called PWM swizzler, allow the four PWM sources from the Intel® Edison to be configured to drive four of the six Arduino PWM pins. Each Intel® Edison PWM can be jumpered to one of three Arduino PWMs.