local dis=peripheral.wrap("back")
local stack
for i,k in pairs(dis) do print(i,k) end
while true do
dis.condenseItems()
stack=dis.getStackInSlot(1)
if stack then -- for i,k in pairs(stack) do print(i,k) end
for i=1,stack.qty do 
rs.setOutput("back",true)
sleep(0.1)
rs.setOutput("back",false)
sleep(0.1)
end
end
sleep(1)
end
