In addition to acting as a GPIO, each pin on the Imp can be configured to one of several hardware specialized functions. While pins may only have one function at a time, they may be reconfigured during run-time to change that function. For example, a pin may first be configured as a DAC and then reconfigured as an ADC. Additionally, not all the pins in a hardware function need to be assigned to that function. For example, pins 8 and 9 could be used as uart1289 and pins 1 and 2 could be used as i2c12.

Pin 6 is reserved for the ID chip and may not be used for any other purpose.

In GPIO mode pins may source or sink up to 4mA.

On IMP-002 solder-down modules, as well as all the IMP-001 pins with all the same functions, the following additional pins and peripherals are available:

(No additional I2C, SPI, DAC, PulseCount, or Wake peripherals are available.)