Wireless temperature sensor transmitter and receiver
####Hardware configuration ######Transmitter:
- Analog temperature sensor TMP36GZ (Analog Devices)
- 8 bit microcontroller ATmega328p (Atmel)
- Wireless transceiver NRF24L01+ (Nordic Semiconductiors)
- Step-up voltage regulator 3.3V
- Other misc components
######Receiver:
- 8 bit microcontroller ATmega328p (Atmel)
- Wireless transceiver NRF24L01+ (Nordic Semiconductiors)
- USB-TTL converter
- Other misc components
Configuration of transmitter and receiver is pretty much the same but the latter doesn't have sensor and voltage reg but has USB-TTL converter instead.
####Brief description of operation ######Transmitter:
- Power on or reset initializes timer interrupt and sensor id is assigned to transmitter
- Most of the time the uC stays in sleep mode and wireless transceiver is powered down
- Every ~2 min a timer interrupt occurs
- uC lights up and LED indicating that it woke up from sleep mode
- NRF24 chip is initialized
- Samples (~100) are read from ADC where analog temperature sensor is connected
- Average is calculated concatenated with sensor id and passed to NRF24 module
- Transceiver sends the data over pipe to receiver
- LED is turned off indicating that transmission is completed
- NRF24 is powered down and atmega328p goes to sleep mode again
######Receiver:
- Receiver is pulling the data from a pipe all the time
- Once the data is available it sends it straight to USART Then it is a task of host machine to read the serial port and interpret the data accodingly.