Networking and communication
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The design used the datasheet of the XIAO ESP32-S3. It includes an integrated antenna that allows basic wireless communication (WiFi/Bluetooth). However, it is also possible to use an external antenna, which helps to improve signal range and stability, especially in environments with interference or longer distances.
During this stage we also explored Meshtastic as a form of wireless communication. It is a system that uses LoRa technology to create a mesh network between devices so each device does not require an internet connection and can communicate over long distances with low power consumption.
However during the setup we had problems when trying to upload the firmware using the web flasher because the system could not connect correctly to the board.
Before starting the tests, the PCB traces were designed, since its implementation is part of later stages of the project focused on bidirectional communication.
The design includes digital inputs (buttons) and external connections such as I2C and GPIO, which will be useful for integrating different modules into the complete system. It also considers communication lines for connecting devices and allowing user interaction with the system.
At this stage, we included the developed board in our PCB inventory as part of the project prototyping stage. This allowed us to better understand the project limits and the necessary adjustments for the next stages.
During programming we had connection problems with the XIAO ESP32-S3 because the system could not recognize the serial port correctly. At first we tried to connect using COM14 but the system showed errors and said the port was busy or did not exist.
After several tests we found that the microcontroller was detected on a different port which was COM15. When we changed the port manually in the command and in the development environment the connection worked correctly.
Wireless communication tests were carried out between two microcontrollers using the XIAO ESP32-S3 as transmitter and the ESP32-C6 as receiver using basic WiFi communication. The ESP32-S3 created a network and the ESP32-C6 tried to connect to it but connection problems occurred because the receiver could not establish communication correctly.
During the tests problems related to the antenna were identified since the communication behavior changed depending on its connection. To achieve correct operation between both nodes it was necessary to use the antenna connection and after this the system started working properly.
After several attempts the connection between both devices was established allowing the correct assignment of an IP address.
By establishing communication between both nodes, the project is based on a wireless communication system between two microcontrollers. The main idea is that the devices can send text messages to each other in real time, working as a simple communication channel.
When one of the devices sends a message, the other receives it and displays it on the serial monitor. This is where the project becomes relevant: the original text is automatically converted character by character into its Braille representation.
Currently, the Braille output is simulated through the serial monitor, which allows demonstrating how the translation process works. However, the intention of the project is to implement this representation in a physical output device, such as solenoid-based Braille cells, capable of generating real tactile dots instead of a digital visualization.