Chapter 6. Other Ways to Connect

I’ve spent most of this book talking about the Redpark Serial Cable, and that’s because it’s the easiest way to connect external hardware directly to your iPhone or iPad. However, before the Redpark cable came along, we had to be somewhat more creative, and in this chapter, I’m going to look at some of the other ways you can connect external hardware to your iOS device.

Using the Network

I haven’t talked about networking very much, but, as we’re all well aware, the availability of ubiquitous data is the thing that changed everything. If we can Internet-enable our sensor, or other hardware, and make it part of the Internet of Things, our iPhone (or iPad) is already well equipped to talk to it.

Using Ethernet

The easiest way to Internet-enable a piece of arbitrary sensor hardware is (probably quite predictably by this stage) by making use of an Arduino. There are several ways you can accomplish this, but if you have a static sensor platform, the simplest way is probably to use wired Ethernet. See Figure 6-1.


An Arduino shield is a board that can be plugged on top of the Arduino PCB, extending its capabilities. It may make use of some, or all, of the Arduino pins. However, those pins that are not used are generally passed through and exposed for other uses. See for a good list of the pin usage of many Arduino shields.

You can buy the official Arduino Ethernet Shield from various vendors, including both the Maker Shed and SparkFun ...

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