Arno's Raspberry Pi Page

A collection of observation, experiments, code, etc.

After doing research on the Web, I found quite a bit of the information available sadly lacking, incomplete or wrong. For areas that interest me, I try to rectify that here.

• GPIO pin power-up behaviour
  Also explains why changing the pull-up/pull-down state often has the potential to do permanent damage.
  
  
• Interfacing GPIOs to 5V logic.
  
  

Code Examples

• Reading the PADS drive strength without memory barriers:
  read_driverstrength.c
• Same as last item with memory barriers. Serves as a test and demo only, if just one peripherial is accessed, memory barriers are not needed:
  read_driverstrength2.c