[RIIM] How many GPIOs does the Border Router have? 9 GPIOs. Last Update: September 29, 2021 September 29, 2021 1185 RIIM Q&A Related Knowledge Base Posts -[RIIM] Is there an acknowledgement (ACK) from the sensor in order to know if the data has been transmitted correctly?[RIIM] To what value is RIIM’s radio RF end matched to?[RIIM] Do I need an external pull-up resistor on the SPI CS (chip Select)?