HydroPWNics

Posting back twice in the same day ha!!!! Laughing aside I finished the Sensor Module from earlier, the source files can be found here along with a PDF of the schematic:

https://github.com/adamjvr/HydroPWNicsHardware

Overall the design didn't take that long, I have working circuits for both the DCDC and FreeScale so all I had to do was copy the schematic and the board took not much longer. In order to keep the costs down I made the PCB as small as possible and kept it to 2 layers. Soon I will order the board from OSHPark and write the firmware using the Motate hardware abstraction system found here: https://github.com/giseburt/Motate Motate is essentially a embedded hardware abtraction library written in C++ sort of like Arduino but with a focus on performance instead, I've played with it before and the FreeScale chip I used is supported by it.

Picture of the Board

This week I have been working on some smaller subsystems that will be integrated into OSHybridFarm. In particular I have been working on the plant sensor package/module PCB. The module consists of a FreeScale MKL05Z16VFK4, 3V3 DCDC regulator, I2C interface, power connector, and 9 sensor connectors. The module is to function as an intelligent ADC/data acquisition node, the goal of such is to sample the analog signals closer to the source to avoid data loss/noise, to avoid running analog sensor signals long distances, and to save inputs on the DyIO modules in the control box. The choice of I2C for serial coms is so that multiple modules can be connected on the same bus and addressed individually, this will also keep wiring in the control box neat by cutting down wires. Another feature that sort of happened by accident was that the pins on the MKL05 for the I2C are also the UART pins, so if the pullups on the I2C pins were not populated on the PCB the module can use UART with a firmware update. So far the Schematic design has been finished, next comes the board stay tuned.

Detail Module Specs:

- FreeScale MKL05Z16VFK4 ARM Cortex M0+

- Ti TPS62162 3V3 1A DCDC Switching Regulator

- 12VDC Power Input (Molex 0705530003)

- I2C Interface (Molex 0705530003)

- 9 powered (3V3) analog sensor inputs (Molex 0705530002)