From LedHed's Wiki
/opt/retropie/configs/n64/InputAutoCfg.ini
[Amazon Fire Game Controller] plugged = True plugin = 2 mouse = False AnalogDeadzone = 4096,4096 AnalogPeak = 32768,32768 DPad R = hat(0 Right) DPad L = hat(0 Left) DPad D = hat(0 Down) DPad U = hat(0 Up) Start = button(11) Z Trig = axis(5-) B Button = button(3) A Button = button(0) C Button R = axis(2+) C Button L = axis(2-) C Button D = axis(3+) C Button U = axis(3-) R Trig = axis(4-) L Trig = axis(5-) Mempak switch = Rumblepak switch = X Axis = axis(0-,0+) Y Axis = axis(1-,1+)