here is SDL keycode for gameshell, yet never plug lightkey so don’t get them =)
#define ka 106 // j
#define kb 107 // k
#define kx 117 // u
#define ky 105 // i
#define kfna 104 // h
#define kfnb 108 // l
#define kfnx 121 // y
#define kfny 111 // o
#define kselect 32 // space
#define kfnselect 269 // -
#define kmenu 27 // escape
#define kfnmenu 8 // backspace
#define kstart 13 // return
#define kfnstart 270 // +
#define klk1 278 // home
#define klk2 280 // pageup
#define klk4 281 // pagedown
#define klk5 279 // end
#define kfnlk1 kfna
#define kfnlk2 kfnx
#define kfnlk4 kfny
#define kfnlk5 kfnb
#define kleft 276 // left
#define kup 273 // up
#define kright 275 // right
#define kdown 274 // down
for missing keys you may check https://github.com/clockworkpi/Keypad/blob/master/keymaps.png
and compare them with https://github.com/SDL-mirror/SDL/blob/SDL-1.2/include/SDL_keysym.h
