Saturday, June 20, 2015

Raspberry Pi and Temperature Sensors

I just got 2 temperature sensors from Adafruit.
Here are mine after I soldered the headers on and wired them up on bread board.

They were very easy to use and didn't take much coding to get them up and running. They are both I2C and I was able to use my existing libraries to talk to them from the PI. I did put up code on github to show how to retrieve the temperature from both. The BMP180 has a few more things (ie. pressure, altitude, etc.) Though, the altitude wasn't very accurate to where I am. I am not sure about the pressure as I am not familiar with that... Either way, a fun project to get up and running!

Pi user space SPI

I finally had some time to play with a OLED (same one as my I2C one; SSD1306 chip), but this interface was SPI. I wanted to learn more about SPI and write a user space program in C++ that would run on my Raspberry Pi and drive the SPI OLED just like I had done for my I2C OLED. Did some digging on spidev and learned a lot. The commands to the OLED were the same as the I2C so I did not have to re-invent the wheel there, but the communication was the only difference.