So the big news is that there is going to be (or already is!) a 2nd revision of the Raspberry Pi PCB, and even bigger is that it’s going to be manufactured (well, assembled) in the UK.

That’s great, but what else? Some of the GPIO pins have changed and that’s not so good for some…

In essence:

• The I2C pins which used to be GPIO 0 and 1 are now GPIO 2 and 3.
• The pin that was GPIO 21 on the edge connector is now GPIO 27.
• There are 4 more GPIO pins available – if you solder on a new connector!

If you are using wiringPi’s native pin numbers then you don’t have to worry. Just get the latest version off the GIT site, install it and re-link your programs.

If you are using the native GPIO pin numbers, then you will need to change your programs – swap GPIOs 0 and 1 for 2 and 3, and 21 for 27.

The 4 new GPIO pins have numbers in the wiringPi scheme of 17, 18, 19 and 20. They are BCM_GPIO pin numbers 28, 29, 30 and 31.

And that’s more or less that!