So .... my ebay loco arrived a bit ago, an Athern SW-7 in SP colors, #2286. This has a DCC decoder unit, a digitrax DN 140 . Has 3 LEDs , headlight front rear and a roof strobe.the violet wire is unused. Now I need a DCC system to test/run this instead of the dc plan. Has anyone used the arduino uno and motor shield /JMRI set up? The loco came from a fallen flag it appears.... on ebay with all his other equipment it looks like... may he rest in peace.