Features:
* Pulse counting from up to four devices via SMA connectors (3.3V to 16V logic levels).
* Data acquisition through UART using a DB9 connector.
*User interface with a 128x160 RGB LCD and four navigation buttons (up/down/left/right) for GUI control, with automatic dimming in low light.
* UART over USB for data transfer.
* microSD card for permanent data storage.
* WiFi for remote data transfer.
GitHub: https://github.com/RobertGawron/HardwareDataLogger/tree/feature/rev_3_0
Due to the availability of low-cost, high-quality PCB manufacturing, home-etched PCBs have become largely obsolete. While the PCB design for this project may be difficult to etch at home, it is still possible. Subparts of the circuit can be assembled on a breadboard, making the process much easier, and the modular software design allows for easy reuse of these components.
The NUCLEO-F103RB serves as the main microcontroller, handling data acquisition, processing, storage, and user interaction. In future iterations, the NUCLEO-F103RB will be replaced by an STM32 chip directly integrated onto the PCB.
The ESP8266 is currently used for data transfer via WiFi and will support FOTA (Firmware Over-The-Air) in the future.
It's good to let the machine handle the tedious work of checking code quality, freeing up more time for the useful and interesting parts of software development.
Embedded development is cool, but constantly flashing the target device for non-hardware-related logic, like the human-machine interface, can be time-consuming and frustrating. To streamline this, a simulation was developed that isolates the firmware not directly tied to hardware, adds stubs for drivers, and includes a GUI. This allows all high-level aspects, such as what's displayed on the LCD, user interaction via buttons, and data parsing, to be tested without the need for hardware.
While this simulation handles the firmware, speed of execution isn't a concern since it focuses solely on high-level logic. For hardware or driver-related issues, traditional methods like using an oscilloscope or logic analyzer are still necessary, as the simulation cannot be used.
Below is a screenshot from the simulation. Note that this is from an earlier version when the device was designed to work exclusively with a Geiger counter. The current simulation doesn't work.