Common 3-pin and 4-pin connector pin outs?

Can anyone tell me what the pin outs are for the Tinkerkit 3-pin (used for digital/analog) connector and 4-pin (1-wire) connector please? These both use the Molex KK 0.1" pitch style connectors. I thought I'd figured it out based on images I'd seen online, but then I saw something conflicting... (!) So better ask instead! Searched the web but didn't find anything definitive!

All this is for a shield I'm building that I want to be compatible with the Tinkerkit standard connector.

Incidentally, if there are other standards than Tinkerkit I'd like to hear about them, but from what I've researched Tinkerkit is the only one I've found, and perhaps most popular (?) with Arduino users.

Many thanks,

The three-pin connectors have Power (red), Arduino Pin (orange), and Ground (black) counting from top to bottom. The 6 labeled I0 through I5 are Analog Inputs. The ones labeled O0 through 05 are Analog Outputs connected to the PWM capable outputs of the Arduino Board:

Pin 11 on the Arduino is O0 on the shield.
Pin 10 on the Arduino is O1 on the shield.
Pin 9 on the Arduino is O2 on the shield.
Pin 6 on the Arduino is O3 on the shield.
Pin 5 on the Arduino is O4 on the shield.
Pin 3 on the Arduino is O5 on the shield.

One 4-pin socket is TWI (I2C) and the other is Serial. The pins seem to be ? (orange), ? (blue), Power (red), and Ground (black) top to bottom. It's not clear which of (orange) and (blue) are used for SCL, SDA, RX, or TX.

Incidentally, if there are other standards than Tinkerkit I'd like to hear about them,

I assume this is the Tinkerkit Sensor Shield being referred to? A link would have been nice. Sheesh, don't those people have a schematic for that thing, without having to search all over the place? If the pin arrangement is as John said

Power (red), Arduino Pin (orange), and Ground (black) counting from top to bottom.

then, to me, they chose the wrong one. Speaking of other standards, much of the world uses a pinout compatible with the most common R/C servo pinout, ie signal-power-ground. Then you can plug servos right in and many sensors too.
http://www.coastalplanes.com/articles/pinout.htm
The Futaba and Hitec arrangements are most common anymore.

The big disadvantage of power-signal-ground arrangement is, you blow up everything if you plug the connector in backwards.

Thanks for the fast replies! http://www.tinkerkit.com/ is what I'm referring to.

When I'm referring to Tinkerkit, I mean either shield or sensors as I'd certainly hope they'd be the same. As you said Dan, a schematic for anything Tinkerkit related seems hard/impossible to find. I've gleaned what I can from photos!!! :fearful: The Tinkerkit 3-wire at http://store.arduino.cc/ww/index.php?main_page=product_info&cPath=16_21&products_id=119 appears to be 1-GND, 2-SIGNAL, 3-VCC going on common colour convention. I was hoping for something a little more certain than that though as I'm basing my design on it. The fact that the connector is keyed means that plugging it in backwards and blowing things up is difficult to do.

The four wire connector is more of an unknown http://store.arduino.cc/ww/index.php?main_page=product_info&cPath=16_21&products_id=273 shows it as 1-BLACK, 2-RED, 3-BLUE, 4-ORANGE. However. .... searching again.... http://www.tinkerkit.com/lcd/ shows it as 1-BLACK, 2-ORANGE, 3-BLUE, 4-RED! Presumably (always risky!) black is GND and red is VCC, but SDA and SCL are goodness knows what, hence why I'm asking if anyone knows.

I've noticed a few generic three wire sensors to be ordered GND, VCC, SIGNAL as you mention Dan, but they're not using keyed Molex KK plugs but un-keyed plugs. I'm thinking if I were to have just bare headers then GND, VCC, SIGNAL might be the best ordering.

If all you ever do is use tinkerkit plugin boards with tinkerkit keyed connectors, then there won't be a problem. If I were going to clone the board, I'd at least buy one first to make sure how it's wired.

If I were going to clone the board, I’d at least buy one first to make sure how it’s wired.

Agree. Thing is in this case I’m not cloning it. The only similarity is that my board has I/O (which many boards do) and uses the same connector as they have used for Tinkerkit - the ubiquitous Molex KK. Why the KK isn’t used on more boards I don’t know - they’re cheap and reliable and keyed so you can’t mess up. The crux of the issue is I don’t want to start a new standard for my board if one already exists. There are already too many standards in the world - driving on the left/right of the road, 220V/230V/240V/110V/115V electricity, 50/60Hz, the list goes on. It would be a lot easier if all these pointless differences had never been started in the first place. Having said that, Tinkerkit gear doesn’t seem to be all that popular, so using it as a defacto standard just because it’s the only standard around might not be wise either. I have been thinking in fact about using the GND, VCC, SIGNAL ordering on my 3-way connectors. People can install just 0.1" pitch bare headers on the board if they want and plug in steppers, sensors, or anything that’s GND, VCC, SIGNAL ordering. As an option (for the extra $0.20 deluxe version) they could install the keyed Molex KK header instead, and have ordering 1-GND, 2-VCC, 3-SIGNAL with a reliable connector that isn’t going to fall out next time it’s bumped. As for the 4-wire I2C, well, I get to ponder that some more… :slight_smile:

oric_dan:
The big disadvantage of power-signal-ground arrangement is, you blow up everything if you plug the connector in backwards.

At least the Tinkerkit shield uses polarized connectors.