I notice on the RAMPS board that a large number of arduino pins are not being used. I even have an LCD on my printer and there still is a large number of pins seemingly available.
I know I would be subject to current limitations, but am I right in assuming that I can use these pins for my own purposes? It would be great if this were so because, for marlin at least, I can control these pins via code and, therefore, very easily from my host software. I believe there are even some PWM pins available which would make it relatively simple, with a small transistor circuit, to control the speed of a couple more fans.
I know I would be subject to current limitations, but am I right in assuming that I can use these pins for my own purposes? It would be great if this were so because, for marlin at least, I can control these pins via code and, therefore, very easily from my host software. I believe there are even some PWM pins available which would make it relatively simple, with a small transistor circuit, to control the speed of a couple more fans.