Hi, I have had Lady Heather running on a small pc for a number of years, controlling a thunderbolt- until the pc quietly died a couple of weeks ago. As I didn't have another spare pc, but I did have a couple of spare raspberry pi's, I thought to have a go at putting it on a Pi. Using the instructions of the LH web site, I had it running quite quickly and with no real drama. Even better, the whole thing (including the t'bolt) now mounts on the back of a 17 inch lcd monitor, making it a very neat installation. The problem came when I wanted to run a small fan for temperature control of the thunderbolt- no matter how I searched, I could not find out which io pins LH uses on the pi to control the fan. The pi doesn't have a "real" serial port, and my software skills are nowhere near good enough to dig through the source code to figure this out. So I would be grateful if someone could tell me which io pins I need to use to control the fan so I can get a bit tighter control of the t'bolts temperature excursions. -- Cheers, Ken bats059@gmail.com 'It seems hard to sneak a look at God's cards. But that He plays dice and uses "telepathic" methods .... is something that I cannot believe for a single moment.' (Einstein's famous quote on Quantum theory) --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus