Fig 6.10 shows the pin description of 10 pin connector, every pin of this connector has specific function. Pin 1 is used as VCC to supply power to the detachable sensor node, while pin 10 is used as ground. The large separation between VCC and ground is provided to avoid short circuit. Pin 2 act as RX pin and pin 3 act as TX pin. Pin 4 is used as the signal pin to know whether the sensor node is attached or detached. Pin 5 to pin 8 is not connected and it is kept for future use in case of system extension or modification.
6.3 Functionality of detachable sensor node
Every detachable smart sensor have two possible states, either it is attached to the DSTIM by the 10 pin connector or is detached from the DSTIM socket. For initial powering detachable sensor should be connected in the DSTIM. While attached detachable sensor draws power from the base. When the sensor is detached from the base, it power up the internal wireless transceiver (CC2500) immediately and checks for sensor…show more content… They are
Query based data transmission: In this mode the sensed data is only send from the sensor node whenever it receive the command from the remote control station. Hence the transmission power of wireless node is reduced due to discontinuous transmission.
Continuous data transmission: In this mode the sensed data is transmitted continuously but the transmitted power is regulated by varying the sample rate. Lower the sample rate lower will be the power requirement.
Deviation mode: In this mode of transmission the sensed data is only sent if there is variation in sensed data in range of ±5% to reduce the transmission power. If the remote sensor node doesn’t send the data for some second then the control station will send query for health signal. If the node responds then it signifies the node is working properly. The duration of sending the query is 5 or 10
