BBB based heating controller
[22 Aug 2016]
I fixed the ULN2803 package and GND on P20. Still need to investigate if there is a pull down resistor needed for Q1
Issues found during assembling the PCB:
- ULN2803 package is incorrect - it should be SOIC18. I will correct the PCB soon
- GND pin in the P20 5V/12V connector is not actually connected to GND
- The heartbeat LED is on...
Circuit to drive the DHT22 temperature and humidity sensor via the SPI bus.
The advantage is, that it uses next to no CPU resources as everything runs in hardware on most platforms.
This allows a multitaking OS like Linux to reliably read the sensor without issues.
This boards should provide SPI I/O expansion based on the MCP23S17.
The boards should be stackable since the layout of the SPI connector is the same for all boards.
The Digital Input and the Digital Relay Output are galvanically isolated.
Prototype has been tested with a Teensy 3.2 but any other SPI capable processor should work.
All In and Out power supply must be provided by external power suppl...
Read/Write WINBOND SPI Based EEPROM Chips Using Any Arduino board. Should work with other brands too.
Link to the post: https://w3epic.com/how-to-read-write-spi-based-serial-eeprom-using-arduino-uno-e-g-winbond-w25x80a/
Source code: https://github.com/Cyberster/SPI-Based-EEPROM-Reader-Writer