Node.js for Embedded Systems

Appendix B. Early Hardware for IoT Systems

Raspberry Pi

The Raspberry Pi is an SBC that was built for students to learn about Linux and programming. But its goals are more ambitious. Jack Lang, chairman of the Raspberry Pi Foundation, said it like this: “We want to revolutionize the desktop.”

To make that happen, the Raspberry Pi iterated a number of revisions. There is the Model 1 and Model 2. Model 1 comes in a version A and B. The differences lie in the amount of RAM, CPU performance, price points, and options for connectvity. For example, while Raspberry Pi Model B allows you to have Ethernet by default, a Raspberry Pi Model A needs some workarounds to set up an Internet connection.

One of the most popular variants of the Raspberry Pi is the B+, as shown in Figure B-1. The core of this board is a Broadcom BCM2835 system-on-chip with integrated CPU, GPU, and a USB port. The boards include an SD card slot so you can run Linux from an SD card.

As you can see, the Raspberry Pi form factor is different from an Arduino. Compared to an Arduino, the “Raspi” has an SD card drive, multiple USB ports, a display adapter, and some pins for digital inputs and outputs. The pinout for the Raspi pin headers are found here: http://pi.gadgetoid.com/pinout. While an Arduino has digital and analog I/O, the Raspi only has digital pins.

The different form factor is one of the reasons you can’t leverage an Arduino project by default on the Raspberry Pi. But besides the difference in physical connections, ...