BBQ Thermometer, smokehouse, oven ... with Raspberry Pi
a couple of weekends that stayed with a friend for smoking ribs and tenderloins ago. The process of smoking, to my surprise it is more laborious and delicate than I thought. A key of this process is the temperature.
The smoker of this friend of mine, of course I had a thermometer, but that day it stopped working, so we had to estimate the horsepower, y así salíó la carne :p
One of the conversations we had throughout the day was to create a thermometer for the smoker and also we could check the temperature remotely. And hence the draft weekend and the reason for this post.
To mount this whole shebang, needed a Raspberry Pi con todos sus avíos (tarjeta de memoria, fuente de alimentación y adaptador inalámbrico), but he needed the / the component / s essential, a sensor that can withstand high temperatures and which can be connected to the Raspberry Pi.
After searching for a while and take a look at a project called HeaterMeter, I decided on a simpler option for me. Me hice con un par térmico (thermocouple), éste en concreto y un circuito amplificador (MAX31855) para hacer de interfaz con la Raspberry Pi.
After welding the components of the circuit and connect the thermocouple at the same, it's time to connect to the Raspberry Pi.
The amplifier uses SPI to communicate with our Raspberry Pi. The Raspberry Pi dispose of 3 List, but only 1 está expuesto a la cabeza de pines (GPIO).
We have 2 ways to communicate with the SPI interface, by hardware or software. The library we use to read the sensor, It allows us to directly use SPI Raspberry Pi, or emulate it by software. The main advantage of the use of software on hardware SPI, is that faster when communicating with the sensor, which in our case is irrelevant, we do not need to read the temperature at very short intervals. Another advantage we have to use the hardware SPI, It is that we free general purpose pins, if we connect more sensors.
Nota: he probado los dos métodos y funcionan exactamente igual y la diferencia de velocidad es inapreciable, but I opted for the second hardware method above reason.
Before getting to rewire, We assume we have installed a system Raspbian, updated and with internet. If you go for the hardware method further you have to activate SPI on your system, since by default is blocked. Esto lo puedes hacer desde la utilidad de configuración raspi-config:
Read the tutorial | CyberHades