Mackie MCU Pro
Set this controller to use the MC protocol. It is recognized automatically by LrControl and PrControl. The display shows the functions in the currently selected layer. If you connect a MCU Pro with USB, it is recognized automatically.
If you connect need even more controls, you can add one or more extenders.
Select MC Mode
In order to use this controller with PrControl and LrControl, it must be set to use MC or Mackie Control mode. To change the mode, hold down both channel 1 and channel 2 SELECT buttons while turning on the power. Press encoder 1 to select Mackie Control.
LrControl uses the time display to display the exposure of the current photo. You get the aperture, shutter-speed and iso value.
One disadvantage of this controller is the poor quality of the display. It tends to fade, especially when using it everyday. Fortunately it is possible to replace the backlight, if you are a bit technical and comfortable opening up electronic equipment, you can do it yourself.
Because I did not want to do this job every two years, I looked for an alternative solution. On eBay you can get a replacement display of much better quality.
For your convenience here are some shopping links.*