rednet.open("right")
function down(depth)
local x = 0
while x < depth + 1 do
if turtle.down() then
x = x + 1
end
end
end

function up(height)
local y = 0
while y < height + 1 do
if turtle.up() then
y = y + 1
end
end
end

while true do
local id, text = rednet.receive()
if text == "banana" then
turtle.digUp()
down(20)
while not turtle.placeUp() do
turtle.placeUp()
end
end

if text == "up" then
turtle.digUp()
up(20)
while not turtle.placeUp() do
turtle.placeUp()
end
end

end