How to sex your Pi

Before you start thinking of a particular scene from the American pie movie, this article is about finding out what pi you have. The term Raspberry Pi gets banded around but there are different versions. You may be thinking that it doesn’t matter but depending on what version you have depends on the GPIO pin headers layout, how much memory, it has, SD card side, etc. Knowing what board you have also helps you to make full use of the memory available as well as making sure you have connected on to the correct GPIO pins (check the GPIO pin diagram below and you can see that although most of the pins don’t move, some of the gpio pins do from the earlier version to the latter).

The Pi 2 introduced a new CPU and additional memory. Now the latest Pi 3 introduces a 64 bit processor and for the first time, a built in wifi.

The variants currently available are :

Model and Pi Revision	256MB	Hardware Revision Code from cpuinfo
Model B Revision 1.0	256MB	0002
Model B Revision 1.0 + ECN0001 (no fuses, D14 removed)	256MB	0003
Model B Revision 2.0 Mounting holes	256MB	0004 0005 0006
Model A Mounting holes	256MB	0007 0008 0009
Model B Revision 2.0 Mounting holes	512MB	000d 000e 000f
Model B+	512MB	0010
Compute Module	512MB	0011
Model A+	256MB	0012
Pi 2 Model B	1GB	a01041 (Sony, UK) a21041 (Embest, China)
PiZero	512MB	900092
Pi 3 Model B	1GB	a02082 (Sony, UK) a22082 (Embest, China)

In order to find out what hardware revision you have you can run the following command at the command prompt or via a terminal window :

 cat /proc/cpuinfo

This will give you a text output something like this :

Processor       : ARMv6-compatible processor rev 7 (v6l)
BogoMIPS        : 847.05
Features        : swp half thumb fastmult vfp edsp java tls
CPU implementer : 0x41
CPU architecture: 7
CPU variant     : 0x0
CPU part        : 0xb76
CPU revision    : 7
Hardware        : BCM2708
Revision        : 0002
Serial          : 000000000abc0ab1

In the above example it’s got the Revision code of 0002. Using the above chart you can see that this is Model B Revision 1.0.

Of course the above is great if you can power up your Raspberry Pi to check what version it is. Sometimes if you are buying at say a show or second hand at a swap meet, yard sale or car boot, physical identification is all you’ll have.

Below is flow chart showing how to physically see the differences between the boards.

 

Please note that when it comes to models B+, B2 and B3, the boards look very similar. The easiest way to see the version on the board like the ones below:

Finally here is the GPIO pin layouts. The Raspberry Pi B+,B2 and B3 all have the same pin layout. Of course the only thing you can tell visually will be if your Pi has 26 or 40 pins. Here is the chart:

Hopefully this guide will help you to identify which Pi you are using.