Bon, je vais laisser ça de côté pour l'instant car je sèche.
En résumé les jeux tournent avec AdvanceMame sur OdroidXU4 (Recalbox 7.0.1), mais plus lents que sur RPI3b (Recalbox 4.1). Pour les jeux peu gourmands ça tourne suffisamment vite, mais le but de mon investissement était de pouvoir jouer à des jeux qui tournaient trop lentement sur mon RPI3b ...
Voilà la dernière version de ma configuration (advmame.rc.origin et dupliquée dans advmame.rc):
#input_map[volume_down] keyboard[1,minus]
#input_map[volume_up] keyboard[1,equal]
device_joystick auto
device_mouse auto
device_video_clock 5 - 150 / 5 - 90 / 5 - 130
device_video_modeline ATSC-1080-59.94p 148.352 1920 1960 2016 2200 1080 1082 1088 1125 +hsync +vsync
dir_artwork /recalbox/share/overlays/advmame
dir_hi /recalbox/share/bios/advance
dir_image /recalbox/share/roms/mame/media/images
dir_memcard /recalbox/share/saves/advance/memcard
dir_nvram /recalbox/share/saves/advance/nvram
dir_rom /recalbox/share/roms/mame
dir_sample /recalbox/share/bios/advance/samples
dir_snap /recalbox/share/screenshots/
display_aspect 16/7
display_resize mixed
display_resizeeffect none
display_vsync no
input_map[coin1] keyboard[0,7] or keyboard[0,5]
input_map[coin2] keyboard[0,o] or keyboard[0,6]
input_map[p1_button1] keyboard[0,lcontrol] or joystick_button[1,0]
input_map[p1_button2] keyboard[0,lalt] or joystick_button[0,0]
input_map[p1_button3] keyboard[0,space] or joystick_button[0,1]
input_map[p1_down] keyboard[0,down]
input_map[p1_left] keyboard[0,left]
input_map[p1_lightgunx] joystick[1,0,x] -joystick[1,1,x]
input_map[p1_lightguny] joystick[1,0,y] -joystick[1,1,y]
input_map[p1_right] keyboard[0,right]
input_map[p1_up] keyboard[0,up]
input_map[p2_button1] keyboard[0,a] or joystick_button[3,0]
input_map[p2_button2] keyboard[0,s] or joystick_button[2,0]
input_map[p2_button3] keyboard[0,q] or joystick_button[2,1]
input_map[p2_button5] keyboard[0,i]
input_map[p2_button6] keyboard[0,k]
input_map[p2_button7] keyboard[0,j]
input_map[p2_button8] keyboard[0,l]
input_map[p2_down] keyboard[0,f]
input_map[p2_left] keyboard[0,d]
input_map[p2_lightgunx] joystick[3,0,x] -joystick[3,1,x]
input_map[p2_lightguny] joystick[3,0,y] -joystick[3,1,y]
input_map[p2_right] keyboard[0,g]
input_map[p2_up] keyboard[0,r]
input_map[ui_configure] keyboard[0,enter]
input_map[ui_down] keyboard[0,down]
input_map[ui_end] keyboard[0,c]
input_map[ui_home] keyboard[0,space]
input_map[ui_left] keyboard[0,left]
input_map[ui_pause] keyboard[0,e]
input_map[ui_right] keyboard[0,right]
input_map[ui_select] keyboard[0,lcontrol]
input_map[ui_up] keyboard[0,up]
misc_quiet yes
misc_safequit no
misc_smp no
sltblgpo/input_dipswitch[attendant_payout] 1750_bfr
sltblgpo/input_dipswitch[hopper_limit] 500
sltblgpo/input_dipswitch[target_percentage] 80