My project was to make a design of a distributed storage and measuring system, which is able to measure on far points, and send the data for a central storage. From the coming to know of the communication protocol I reached to design the test panel, and the software.
I started the work with research of literature. I analyzed some communication protocols, checked up the components which are suitable for realize the project. While in the panel it’s enough a protocol, which able to short transferring and receiving data (like I2C, LIN bus, or SPI), among the panels required a protocol, which is able to transfer and receive data for long distance (like CAN bus). After the choose of the circuit’s components I chose from the protocols the SPI for the data storage, and CAN bus for transferring and receiving data.
During the design the first step was the system plan. Here I paid attention that the panels contain the all functions, which required. After this I must have selected the right components. Microcontrollers control the panels (one storage and one or more measuring panels), and my choice was the family of PIC32. They have SPI and CAN modules, so these protocols were able to realize the project. To the controller it needed peripherals to the measuring, communication and storage. On the panels are so far CAN transceiver, temperature sensor, voltage reference, CAN terminal, and oscillator. The system has also SD Card cell, that the storage will be able to function without computer. There is a possibility to transfer the data direct for the PC through an USB port.
The next step was the schematic drawing, than I handled with the design of the Printed-Wiring Board, which have completed. I aspired to make small panels to spell money. After I came to know with the Microchip’s development environment and with the software modules for the function with help of the Microchip’s PIC Family Reference Manual. I came to know the A/D converter, CAN, SPI module, USB protocol and the software directory, which manages the FAT file system.