ESP8266 Microcontroller Application in Wireless Synchronization Tasks

The operation of UDP protocol in the Wi-Fi network and Espressif ESP-NOW protocol is studied. In the first case, an external Wi-Fi access point is used to communicate between two ESP8266 microcontrollers, and in the second case, both microcontrollers operate as paired devices. The standard libraries of the Arduino IDE programming environment are used in the source codes. The local time of sending and receiving is saved during the packets exchange, on the basis of which the processing time and delay of the packet, as well as, the system clock discrepancy of both ESP8266 microcontrollers are calculated. To obtain experimental data, 5000 packets are exchanged. The evaluation is carried out by applying various operating frequencies of the microcontroller (80 MHz and 160 MHz), as well as the operating library version of API for ESP8266 application (Non-OS SD 2.2.1 and Non-OS SDK pre-3). The obtained results demonstrate the best values for short packets when ESP-NOW protocol is used, however, the deviation can be obtained in almost 25% of cases even with absence of transmission/reception error.