shaftElevatorTop

local modem = peripheral.find("modem")
if (modem == nil) then
    print("no modem link")
    return
end
modem.open(0)

local upState = false
local function switch()
    redstone.setOutput("top",upState)
    upState = ~upState
end

local function redstoneCheck()
while true do
    os.pullEvent("redstone")
    printf("redstone")
    switch()
end
end

local function modemcheck()
while true do
    local event, modemSide, senderChannel,
        replyChannel, message, senderDistance = os.pullEvent("modem_message")
    switch()
    printf("modem")
end
end

parallel.waitForAny(redstoneCheck,modemcheck)