moving_dashes.lua

-- local function do_write(p, x)
--  p.setTextScale(5);

--  p.clear()
--  for h = 1, 8 do
--      for w = 1, 12 do
--          if (h + w) % 2 == x then
--              p.setCursorPos(w, h);
--              p.write('/')
--          end
--      end
--  end
-- end

local function do_write(p, x)
    p.setTextScale(1);

    p.clear()
    for h = 1, 40 do
        for w = 1, 61 do
            if w % 3 == x then
                p.setCursorPos(w, h);
                p.write('|')
            end
        end
    end
end

local function main()
    local p = peripheral.wrap("bottom")

    while true do
        do_write(p, 0)
        sleep(0.1)

        do_write(p, 1)
        sleep(0.1)

        do_write(p, 2)
        sleep(0.1)
    end
end

main()