While I was testing your PWM solution I discovered that the pins connected to chip1 all give 3,3V except pin 11(?). All the other pins connected to chip0 en Chip2 only give 3,29V. I noticed this first with a LED connected to one of those pins (chip0 or chip2) was not as bright as when connected to a pin of chip1. Is this normal behaviour or is there something wrong with my board?