Pimatic and GrovePi

Thomas Meier

I have a RaspberryPi 3 with a GrovePi board and a few sensors and relays hooked up to it. Currently I run everything via a self written PHP/Python script to read and control these sensors. Since GrovePi offers node.js APIs I’m thinking about getting into node.js programming and I’ve just stumbled across pimatic today in search of a home automation application example to look at. Looking at pimatic it seems that it already does pretty much everything I try to develop myself so why re-invent the wheel?

I haven’t found any evidence that pimatic supports grove sensors/actors or the GrovePi extension board. What I have found thou is that people are alredy using the same DHT22 Temperature/Humidity sensors I’m using and found one refenece in the forum to a grove relay. I would say the hardware I have is pretty much the same pimatic supports. So I’m prety sure that integrating GrovePi into pimatic is just a small matter of getting them to “talk to each other” basically. But since I’m totally unfamiliar with pimatic or node.js yet I wouldn’t know how to start doing that myself.

So to ask quite simple. Is there an esay way for me to use pimatic with my GrovePi board and sensors/actors or do I really need to get into node.js codeing myself for that to work?

Freekwilly

I believe the whole GrovePi family is based on a simple breakout board/shield, am I right?
I built such a breakout board myself and as you correctly mentioned many people around here are using DHT-22 sensors for humidity/temperature measurement, including me.

You simply have to figure out which of your ports resembles which GPIO Pin on your raspberry pi (but you actually do know already, since you have your customised scripts) and then use the DHT plugin for pimatic. That’s what I’m doing on my self built breakout board at least

Thomas Meier

Wow, thanks for the fast reply!
Unfortunately GrovePi is a bit more than just a breakout box that I could talk to directly with GPIO. It has an ATmega328 on there which is connected to the GPIO so communication with the sensors/actors is through the controller. I read/write these sensors/actors via a library GrovePi offers for python and node.js besides other languages. The elementary functions are pretty much the same as for GPIO. DigitalRead/Write or AnalogRead/Write against a pin on the GrovePi board. The rest are just helper functions translating the raw readings from different sensors into usable formats. Nothing that pimatic hasn’t already implemented like in the DHT plugin.
So that’s why I think some interface plugin would probably be needed in pimatic to talk to GrovePi like it does to GPIO. Besides that I would have to find a plugin for my Soil Moisture and Air Quality sensor. These are just analog sensors giving single analog readings so I’m sure there is a generic plugin for that already.
I’m not sure if I should open another topic regarding the interface plugin in the Plugins subforum. My question covers a bit of both Hardware and Software.

mwittig

@Thomas-Meier said in Pimatic and GrovePi:

I have a RaspberryPi 3 with a GrovePi board and a few sensors and relays hooked up to it. … Looking at pimatic it seems that it already does pretty much everything I try to develop myself so why re-invent the wheel?

No, you may want to try pimatic-johnny-five which contains (limited) support for the GrovePi board. At least, basic digital & analog I/O and PWM should work. See the following thread for background: https://github.com/rwaldron/johnny-five/issues/971.

I haven’t found any evidence that pimatic supports grove sensors/actors or the GrovePi extension board. … So to ask quite simple. Is there an esay way for me to use pimatic with my GrovePi board and sensors/actors or do I really need to get into node.js codeing myself for that to work?

Presumably most sensors/actors like Temperature/Humidity sensors, relays, and such are just basic modules which contain a few additional electrical components. I think the Temperature/Humidity sensor is likely to work with pimatic-dht-sensors. Another route to follow again is pimatic-johnny-five as johnny-five provides provide dedicated support for several grovepi sensors. So, they can also be used without having the grovepi board in the loop. Note, however, the supported device classes is still somewhat limited. If you have specific needs like integrating servos, please let me know. I should also say that support for DHT22 is somewhat limited. It can only be integrated using an dedicated Arduino backpack which provide an I2C interface for DHT22 1Wire. So, for the Temperature/Humidity sensor pimatic-dht-sensors is perhaps the best option.