On my previous RTI systems, the only feedback I get from the controller during the operation is a "beep" when each LED is turned on. Not a lot of information, and also not really necessary, since I get a shutter sound from the camera indicating that it's firing, which indicates that things are working. I've been thinking about adding a more useful feedback tool, and finally broke down and bought one of those little 0.96" 128 x 64 I2C OLED displays that you can pick up for less than $10 if you look. Adafruit has a nice tutorial on their use, along with sample code. Connected the board to a spare Arduino Mega I had lying around, uploaded the test code (after a few modifications), and it worked fine. Then hooked it up to one of my older RTI systems, and modified the control code to add display support. Didn't work. Spent an hour debugging code, checking connections - nope. Connected it back up to the first Arduino, and it worked fine. Hmmm. Grabbed the Arduino that will be controlling the current build being documented, uploaded the code, and tested it. Yup, worked. Sometimes it really is the hardware's fault.

Anyway, here's a couple of pics of the display in action plugged into the MOSFET driver shield that's part of the new RTI system being built. Still have to figure out which parameters to display and how, but I'll get that working when the system is fully assembled. At a minimum, it will show how far along in the process you are, and how much time is left. Full instructions will be written up, including how to install it in the control box ... as soon as I figure out how to do that.