Hardware selection
Materials used in this project:
| Seeed XIAO ESP32C3 | LEDs | Buzzer |
|---|---|---|
 |  |  |
| Switches | LED strips | Water pump |
|---|---|---|
 |  |  |
Note: These peripherals are used in our system for illustration, and they may be replaced by other device/appliance.
| Features | ESP32C3 | ESP 8266 | STM32 with Wi-Fi Module |
|---|---|---|---|
| ESP-NOW Protocol Support | Native support | No native support | Typically unsupported |
| Power Efficiency | High, supports deep sleep modes | Moderate, less efficient | Varies, generally less efficient |
| Performance and Features | High, RISC-V architecture | Moderate, Tensilica Xtensa | Varies, depends on configuration |
| Development Ecosystem and Community Support | Extensive, strong community | Good, less advanced | Strong for STM32, complex configuration |
| Cost and Availability | Cost-effective | Cheaper, fewer features | More expensive, complex integration |
For this project we have chosen to work with the ESP32C3. The ESP32C3 is better suited for wireless switch module due to its native support for the ESP-NOW protocol, improved power efficiency, better performance, and more robust development ecosystem compared to the ESP8266 and STM32 with a Wi-Fi module.
Hardware design
| Transmitter | Receiver |
|---|---|
 |  |
The ESP-NOW protocol requires two ESP32C3 boards, one to act as a transmitter and another as a receiver. Each board was connected to their out-of-the-box antennae to increase SNR.
The transmitter is wired to accept input from 3 switches. Each button when pressed would toggle the associated pins on the receiver sides.
The receiver is wired to 3 LEDs and when data is received from the transmitter, it would toggle the associated pins either from (HIGH to LOW) or (LOW to HIGH). The 3 LEDS, are just to indicate switching.
In the indoor farm application, one of the receiver output pins is wired to a buzzer. All output pins were then wired to the signal side of a relay board.