Apologies if this question has been covered previously, I've tried to search the web/forum but I can't see a similar question.
Before attempting to connect a picaxe (08M2) to the RPi; I thought I'd just double check the voltage pins on the RPi GPIO pins. (3.3V and 5.0V so I don't kill my 08M2)
When I put my multimeter on the 5v + GND pins I read 0V (When RaspBMC is running.)
I thought maybe the GPIO needed to be 'switched on' so I tried the above while running Debian. Doing this also gives 0V but also causes the RPi to reboot.
Is this to be expected? I've tried powering the RPi from a powered USB Hub and Blackberry Phone Charger... same outcome... any ideas what am I doing wrong?