The interface between the hardware and the Raspberry Pi media centre is managed by a piece of software called LIRC (Linux Infrared Remote Control). This is pre-installed on most recent Raspberry Pi distributions and is included in the Rasbmc distribution, so there is nothing to install, however, there is some setting up to do.
To make sure that the IR hardware is correct, we can connect to the Raspberry Pi running Rasbmc using SSH, which is automatically enabled on this distribution.
You can find the IP address of the Raspberry Pi using the XBMC System Info page.
To be able to test the IR receiver without XBMC, you need to make sure that the IR remote feature is turned off, or you will not be able to use LIRC from the SSH. So run the Rasbmc Settings program and make sure that the option Enable GPIO TSOP IR Receiver is disabled.
If you needed to change this you will need to reboot.
Now connect to the Raspberry Pi using SSH and issue the commands shown below:
Now hold the remote in front of the receiver and you should see a series of 'pulse' / 'space' messages appear each time you press a button.
Congratualtions! The IR receiver is working.