J'ai un peu regardé la chose.
J'ai regardé DatarefTool en scrutant : pikitanga/ocusbmapper/usb1/input/digital
Quand j'actionne un interrupteur je vois par exemple :
[0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]
le 6ème nombre est 1. Du coup, j'ai essayé :
	
	
	
		Code:
	
	
		--[[
*****************************************************************************************
* Program Script Name    :    RJ85.EFDE_OVH
*
* Author Name            :    Emmanuel v1.00
*
*   Revisions:
*   -- DATE --    --- REV NO ---        --- DESCRIPTION ---
*      31/01/2020   1.0.0                Création
*
*
*
*
*****************************************************************************************
--]]
--*************************************************************************************--
--**                                   XLUA GLOBALS                                   **--
--*************************************************************************************--
--[[
SIM_PERIOD - this cont'ains the duration of the current frame in seconds (so it is alway a
fraction).  Use this to normalize rates,  e.g. to add 3 units of fuel per second in a
per-frame callback you’d do fuel = fuel + 3 * SIM_PERIOD.
IN_REPLAY - evaluates to 0 if replay is off, 1 if replay mode is on
--]]
--*************************************************************************************--
--**                                    CONSTANTS                                     **--
--*************************************************************************************--
USB_DEVICE = 1
--*************************************************************************************--
--**                                 GLOBAL VARIABLES                                 **--
--*************************************************************************************--
--*************************************************************************************--
--**                                 LOCAL VARIABLES                                  **--
--*************************************************************************************--
local simDR_battery = -1
local ovhDR_button_YD_on = -1
local seatBelts = -1
local ovhDRavionics = -1
--*************************************************************************************--
--**                              FIND X-PLANE DATAREFS                                 **--
--*************************************************************************************--
simDR_battery                = find_dataref("sim/cockpit/electrical/battery_on")
-- switch
ovhDR_button_batt_on        = find_dataref("sim/cockpit/engine/APU_running")
ovhDR_button_YD_on            = find_dataref("sim/s'ystems/yaw_damper_on")
seatBelts                    = find_dataref("sim/cockpit/switches/fasten_seat_belts")
ovhDRseatBelts                = find_dataref("sim/s'ystems/seatbelt_sign_toggle")
ovhDRavionics                = find_dataref("sim/cockpit/electrical/avionics_on")
--*************************************************************************************--
--**                                FIND X-PLANE COMMANDS                                **--
--*************************************************************************************--
--*************************************************************************************--
--**                               FIND CUSTOM DATAREFS                                  **--
--*************************************************************************************--
usbDR_input_digital          = find_dataref("pikitanga/ocusbmapper/usb" .. USB_DEVICE .. "/input/digital")
--[[
usbDR_input_analog           = find_dataref("pikitanga/ocusbmapper/usb" .. USB_DEVICE .. "/input/analog")
usbDR_input_analog_notshow   = find_dataref("pikitanga/ocusbmapper/usb" .. USB_DEVICE .. "/output/analog/notshow")
usbDR_output_allon           = find_dataref("pikitanga/ocusbmapper/usb" .. USB_DEVICE .. "/output/allon")
usbDR_output_dspl            = find_dataref("pikitanga/ocusbmapper/usb" .. USB_DEVICE .. "/output/dspl")
usbDR_output_dspl_brightness = find_dataref("pikitanga/ocusbmapper/usb" .. USB_DEVICE .. "/output/dspl/brightness")
usbDR_output_leds            = find_dataref("pikitanga/ocusbmapper/usb" .. USB_DEVICE .. "/output/leds")
--]]
--*************************************************************************************--
--**                               FIND CUSTOM COMMANDS                               **--
--*************************************************************************************--
--*************************************************************************************--
--**                         CREATE READ-ONLY CUSTOM DATAREFS                            **--
--*************************************************************************************--
--*************************************************************************************--
--**                        READ-WRITE CUSTOM DATAREF HANDLERS                          **--
--*************************************************************************************--
--*************************************************************************************--
--**                        CREATE READ-WRITE CUSTOM DATAREFS                         **--
--*************************************************************************************--
--*************************************************************************************--
--**                              CUSTOM COMMAND HANDLERS                             **--
--*************************************************************************************--
--*************************************************************************************--
--**                               CREATE CUSTOM COMMANDS                               **--
--*************************************************************************************--
--*************************************************************************************--
--**                              X-PLANE COMMAND HANDLERS                            **--
--*************************************************************************************--
--*************************************************************************************--
--**                              REPLACE X-PLANE COMMANDS                               **--
--*************************************************************************************--
--*************************************************************************************--
--**                               WRAP X-PLANE COMMANDS                               **--
--*************************************************************************************--
--*************************************************************************************--
--**                                OBJECT CONSTRUCTORS                                  **--
--*************************************************************************************--
--*************************************************************************************--
--**                                   CREATE OBJECTS                                    **--
--*************************************************************************************--
--*************************************************************************************--
--**                                  SYSTEM FUNCTIONS                                **--
--*************************************************************************************--
function process_switches()
    if usbDR_input_digital[5] and simDR_battery == 0 then
        simDR_battery[1] = 0
    end
    if usbDR_input_digital[4] == 1 then
        seatBelts = 2
    end
    if usbDR_input_digital[4] == 0 then
        seatBelts = 0
    end
end
function process_buttons()
end
function process_dials()
end
function process_leds()
end
function process_displays()
    --[[
   
    0 - 9     = corresponding digit
    10        = blank
    11        = -
    12 - 15 = varies depending on the hardware device eg MCP 13 is an "A"
   
    --]]
end
function process_encoders()
end
--*************************************************************************************--
--**                                XLUA EVENT CALLBACKS                                **--
--*************************************************************************************--
--function aircraft_load() end
--function aircraft_unload() end
--function flight_start() end
--function flight_crash() end
function before_physics()
    process_switches()
    process_buttons()
    process_dials()
    process_leds()
    process_displays()
    process_encoders()
end
--function after_physics() end
--function after_replay() end
--*************************************************************************************--
--**                                SUB-MODULE PROCESSING                                **--
--*************************************************************************************--
-- dofile("")
	 
 
Ça marche pas.