IDE harddrive cables

There is a neat way to connect arduino to your breadboard and avoid all those crazy and loose jumper wires: the phi-connect shield.

The phi-connect stackable version can be stacked below shields so you can benefit from both shield functions and a large breadboard and easy to switch projects in and out.

As you can see from the top to bottom is an arduino shield (phi-2 shield), phi-connect shield that passes all arduino connections to the breadboard via an IDE hard drive cable, and the arduino.

Now you know how useful an old IDE hard drive cable can be. But hold on before you star using just any IDE hard drive cable yet, because you need to get the right cable or otherwise puff, short circuits!

Here is why: newer IDE cables (aka 40-connection 80-wire ribbon cables) are made so that many of the connections are all connected together to ground. So if you’re not careful, you will short your circuit or at least ground some signals and make your project malfunction. So what kind of IDE cable should you use? 40-connection 40-wire cable. Make sure you could 40 wires on the ribbon. You can also use old floppy drive cables, which are 34 wires, so less connections.

Here is a comparison of 40-wire (left, often having 28AWG marked on it) and 80-wire (right, often having 30AWG marked on it) IDE cables, make sure use the 40-wire!!!

You can connect to an LCD easily with such a ribbon cable to arduino.

(If you look closely I actually used an 80-wire cable, which made my life much harder. Don’t do it!)

Here is the wiki page on this topic:

Painful details if you want to know, why I don’t recommend 80-wire IDE cables:

OK, that “identical” look between the two versions (40-wire and 80-wire) could fool you and certainly did me about a year ago but after some serious problems with my very first try on an LCD I pulled out my multimeter and measured. Those pins “2,19,22,24,26,30, and 40” to are indeed all tied together, plus two pins are N/C too! The newer 80 wire ribbon cables are older 40 ribbon cables are 30AWG (thin wires) and 28AWG (thicker wires). A closer look will be enough to tell, although only if someone has one type at hand then they’ll have to read (hint: keyword 30AWG on cable) or count (hint:superfine permanent marker comes handy).

The media are no different, plain cables. But the connectors are very different if you pry them open. The oldie 40-wire version has two rows of sharp cutters ( I don’t have a name for the part that cuts through insulation and makes metal-to-metal contact). Top row is odd pins and bottom row is even pins (or the other way around if you hold protrusions on the connector downward. All those are individually connected to their female pins. If you open a connector on a newer 80-wire version, there are three rows of sharp cutters. Besides the top row (odd pins) and bottom row (even pins), the middle row is all interconnected one piece of metal. It cuts every other wires, plus those positions corresponding to pins 2,19,22,24,26,30, and 40 on the female connector. The “41-80” wires are meant to be every other wire on the ribbon cable and are also grounded for higher speed communication. They don’t make to the connector’s other side, only the first 40 do (minus 1 behind a mechanical key).

When I was designing my phi-connect shield for prototyping breadboard, I studied these two types of cables over and over with online materials and checked every ground pin with my multimeter and I decided to go with 40-wire cables for simplicity. Thicker wires and simple connection scheme against benefit of every other wire being grounded but complex connection scheme I made my choice. I think I did my homework.

Phi-connect is available

After some long planning, prototyping and production, the phi-connect system is available for sale. This is a big time saver and headache remover for arduino users. Connect and disconnect your arduino from a project and switch to a different project in seconds. Please check out its own blog page for more details.


Here is the list of online stores that sell the kits:

Phi-connect is coming soon!

After some long wait, I was assured that the phi-connect has been manufactured and shipped. Here’s pictures supplied by the manufacturer, not the best, but at least something is better than nothing.

This will go on the Arduino:

This goes on the breadboard or you can solder on it for your permanent installation.

You can see everything is marked clearly enough. I don’t have space to mark PWM pins as “PWM” so I got a little creative and used a “)” on each pin that is a PWM. There is also a legend “PWM)”, which reminds you the “)” pins can do PWM.

As you can see, there are two places on the small board with 5V and gnd. Yes, if you solder pins on them, you can plug them directly in the power buses on your breadboard! They also improve the mechanical strength of the board.

I will make an announcement once they reach the online stores ready for grabs. Besides, I’m stilling looking for picture exchanges. If you have a messy project with crazy wires on your board, send me a pic. I can send you the phi-connect in exchange for a couple of pictures of well-organized project with the help of phi-connect. The amount of this exchange is limited so leave a message if you want the exchange.


%d bloggers like this: