The family input contract: move a hardware sprite with the d-pad. The square is
a sprite (surface 2) - spr(1, x, y) pushes the built-in solid-block tile
onto the shadow OAM, DMA'd to the PPU every frame. Runs at 60fps (_update60).
local x = 120
local y = 112
function _update60()
if (btn(1)) then x += 2 end -- right
if (btn(0)) then x -= 2 end -- left
if (btn(3)) then y += 2 end -- down
if (btn(2)) then y -= 2 end -- up
x = mid(8, x, 240)
y = mid(16, y, 208)
end
function _draw()
cls(12) -- sky-blue backdrop
spr(1, x, y) -- the movable square
end
Real frame captured from the fceumm core (2x integer scale of native 256x224).
neslua build main.lua -o pad-square.nes
neslua run main.lua # arrow keys move the square