8

There exists a large variety of sensors in the Grove System. Usually these are accessed via a special shield (Grove base shield).

Can I access these sensor directly without a shield. In particular I am interested in using them with an Arduino Pro Mini. My guess is that one definitely needs the 5V version of the Mini, but other than this? How fiddly is it to use these sensors directly?

I am interested in using the Grove dust sensor, but I am also would like to operate a Grove 4 digit display.

4

Groove Schematic From the wiki.

Above is a schematic of a Groove shield. You can see that each of the connectors has two digital pins connected to it and then V (5V) and G (GND). The last two you can connect normally to an Arduino. The first two you connect to the pins that are used in your sketch.

Say it says to connect the connector to the top left DIGITAL pin on the board (D6/D7). You'll 7want to connect the pins as followed: Black → GND, Red → 5V, White → D7, and Yellow → D6.


Notes:

  • The shield overlaps the pins (i.e. 3-4, 4-5), so that might make things confusing. I think that is a design flaw. If it needs two pins, it should have two connectors. In the current state, you can connect two things together. I don't really know how to figure out if it uses all of the ports attached or not. If you don't have to, I would try not to overlap any two grooves. You would do this by using two digital ports for every groove "module."
  • You'll also need to have a adapter cable (Link from TheDoctor's Answer.)
  • For analog connections, it applies the same way as digital. G is ground, V is 5v, and A# is an analog pin.

Inferencing it:

There's no real cookie cutter way to connect to them. However, the wiki seems to be a decent resource once you figure out how to navigate it. The dust sensor you mentioned seems to ONLY use digital pin 8. It was connected to the D7/D8 connector on the Groove shield, so the yellow wire could be ignored since it was never used in the sketch.

It's hard to do much with this system: it's poorly documented and not uniform at all. Plus, some boards could cause problems that could even lead to damaging components. I would say look at something else.

Sharp pin 1 (V-LED) => 5V (connected to 150ohm resister) Sharp pin 2

(LED-GND) => Arduino GND pin Sharp pin 3 (LED) => Arduino pin 2

Sharp pin 4 (S-GND) => Arduino GND pin Sharp pin 5 (Vo) =>

Arduino A0 pin Sharp pin 6 (Vcc) => 5V

I can't seem to find the cord for it, but I'm sure there are many others like this online. (It lists the cable needed: a 6-pin, 1.5mm pitch connector. That doesn't seem too hard to find).

  • Here is a 4x7 segment display for much cheaper. It does use a lot of pins and need resistors, but multiplexing and resistors aren't that hard to figure out. That's outside of the scope of this question. There might be some other board with a built in IC for controlling a display like that, but I can't seem to find one now.
3

Grove sensors use a special socket, a 4 pin JST with two power lines and two data. you would have to make your own board/terminal to get them to connect to a mini.

What you could do is use a Grove proto board, which converts the JST terminals onto .1" pins suitable for connecting to the Mini. There is also a litle proto area if you want it.

You could also use an adapter cable, which would not have a bulky protoboard along with it. The terminals could be soldered directly to the Mini.

  • I was thinking of using an adapter cable - hooking up the grove sensor does not seem such a big problem. However how can I access/communicate with them? – A.Schulz Mar 4 '14 at 15:25
  • 1
    @A.Schulz: Exactly the same way as if the Grove connector wasn't there. The hardware is still the same, only the pins have been changed. – Ignacio Vazquez-Abrams Mar 5 '14 at 3:30
  • Not every Grove sensor uses all 4 wires. Most of the basic analog ones use SIG,NC,VCC,GND - where NC means Not Connected. On the Seeed Studio wiki, they publish Eagle files for most of the sensors. If you check them, you'll confirm NC is not connected to anything. – Mike Causer Jan 28 '15 at 23:57
  • The reason some are 3 and 4 wires is so they can use a common connector. If you use a 4 wire sensor, such as an I2C sensor, you cant use the adjacent socket on your Grove base shield, as adjacent sockets share 1 pin. Socket labelled D4 contains pins D4,D5. Socket labelled D5 contains D5,D6. D5 is common between the two sockets. – Mike Causer Jan 28 '15 at 23:59
1

I'm pretty sure you could just take the signal cable from the dust sensor and plug it directly into your mcu digital pin of choice and then wire the Vcc and Gnd as well. I'm working with a CO2 sensor and don't really want the shield overhead.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.