local component = require("component") --require component in order to use the component API
local sides = require("sides")
local redstone = component.redstone -- create the variable "redstone" (which is shorter than typing out component.redstone)
local function wait(seconds)
  local begin = os.time()
  repeat
    computer.pullSignal(0.05)
  until os.time() - begin >= seconds
end
while true do
 redstone.setOutput(sides.left, 15)
 wait(0.1)
 redstone.setOutput(sides.left, 0)
 wait(0.1)
end