WASD turtle control

term.clear()
x,y = term.getSize()

-- screen display
term.setCursorPos(3, y/3-1)
print("Q")
term.setCursorPos(x/2, y/3-1)
print("W")
term.setCursorPos(x-3, y/3-1)
print("E")
term.setCursorPos(1, y/3)
print("Quit")
term.setCursorPos(x/2-3, y/3)
print("Forward")
term.setCursorPos(x-5, y/3)
print("place")
term.setCursorPos(x/5, y/3*2)
print("A")
term.setCursorPos(x/2, y/3*2)
print("S")
term.setCursorPos(x/5*4, y/3*2)
print("D")
term.setCursorPos(x/5-2, y/3*2+1)
print("Left")
term.setCursorPos(x/2-2, y/3*2+1)
print("Back")
term.setCursorPos(x/5*4-2, y/3*2+1)
print("Right")
term.setCursorPos(1, y-3)
print("[Shift]")
term.setCursorPos(3,y-2)
print("Up")
term.setCursorPos(1, y-1)
print("[Ctrl]")
term.setCursorPos(x/2-3, y-1)
print("[Space]")
term.setCursorPos(x-8, y-1)
print("[<-] [->]")
term.setCursorPos(2, y)
print("Down")
term.setCursorPos(x/2-1, y-1)
print("Dig")
term.setCursorPos(x-6, y-1)
print("Slot")

--select slot 1 by default
turtle.select(1)
slot = 1

--button selection
while true do
  event, p1 = os.pullEvent()
  if p1 == "a" then
    turtle.turnLeft()
  elseif p1 == "s" then
    turtle.back()
  elseif p1 == "d" then
    turtle.turnRight()
  elseif p1 == "w" then
    turtle.forward()
  elseif p1 == 42 then
    turtle.up()
  elseif p1 == 29 then
    turtle.down()
  elseif p1 == 57 then
    turtle.dig() -- change to turtle.attack() for melee turtle
  elseif p1 == "q" then
    term.clear()
    term.setCursorPos(1,1)
    break
  elseif p1 == "e" then
    turtle.place()
  elseif p1 == 205 then
    slot = slot+1
    if slot > 16 then
      slot = 1
      turtle.select(slot)
    else
      turtle.select(slot)
    end
  elseif p1 == 203 then
    slot = slot - 1
    if slot < 1 then
      slot = 16
      turtle.select(slot)
    else
      turtle.select(slot)
    end
  end
end