Grove is both a connector type and an architectural specification - possibly created by Seeed?
The Grove connector pinouts you use on the GoPiGo - and possibly other products - seem to match the Grove pinouts specified by Seeed.
Question:
Do you implement the Grove architecture as specified by Seeed?
(Assuming the existence of compatible libraries)
Will any Grove device, manufactured by anyone work on the GoPiGo, etc.? (i.e. If I buy a Grove “button” or “temperature sensor” from someone who may have a sensor you don’t sell, will it work? Or do I risk burning out the GoPiGo3 board?)
Example
Both you and Seeed sell a Grove “button”.
The Grove button supposedly can be used as an input device on either of the two Analog/Digital connectors on the GoPiGo.
You don’t publish a schematic for your button - at least not that I have found.
Seeed does. That, (and other literature), indicates it’s a normally open switch with a 10k pull-down from the signal pin to ground. When pressed, there is a direct connection from the signal pin to the + power pin.
Experimenting with the analog/digital pins on the GoPiGo3 board seem to indicate that the inputs “float” (are not pulled in either direction when open), because a long, (50 cm), wire connected to a pin causes the digital output to flip back and forth.
My previous experience with electronics indicates that a circuit pin - unless clearly specified otherwise - can be shorted to ground but requires a pull-UP resistor to VCC to prevent blowing the output on the pin.
So, to what extent, if at all, do you implement the Seeed Grove specification?
I think we find ourselves in a gray area - initially, we wanted to support a vast majority of the Grove devices from Seeed (starting with the original GrovePi, going with the GoPiGo and then the more recent reiterations of them), but now we’re putting more emphasis on our own add-on devices (the distance sensor, the temperature/humidity/pressure sensor, the light and color sensor, the line follower). So the emphasis is slowly shifting towards ours.
Now, we still support basic Grove (Seeed-based) devices, such as the button, a slider, LEDs and so on: basically anything that deals with digital/analog input/output and we will continue to do this in the foreseeable future. Without going into details, I don’t think you risk burning out the GoPiGo3 board just by plugging in this type of sensors that have been sold by Seeed.
This may return to bite you later on since any reasonable person building stuff will assume that - because you are supporting the Grove connector, you are supporting the entire interface. (At least IMHO)
Supporting the entire interface isn’t necessarily a bad idea - people who don’t have a Dexter robot can still buy, and use, your interesting devices.
Without going into details? Unfortunately, “The Devil’s in the details”
In theory - note the emphasis on the “in theory” part - any i2c, digital, or analog device is compatible with Dexter’s products.
Sticking points:
Watch the I/O voltages, the GPG and the Pi itself use 3.3v logic. 5v logic is virtuallly guaranteed to toast your device.
“Native” software support may be limited or non-existent. If you don’t mind bit-banging or creative coding, go right ahead - and don’t forget to let us know how it worked out!
