Added text based setting of GPIO allowing in/out configuration and refactor code

src/BeagleBone/GPIO.jl

-"""
-Lowest form of communication woth the GPIO pins. The available pins are
-listed in the "channel" parameter, and appear as directories in /sys/class.
-Any of these GPIOs can be run in various ways, with any operation specified
-by a sequence of three entries
-
-  (channel, operation, entry) = (int32, int32, String)
-
-For instance, if the GPIO "gpio30" is to be configured as a output pin and set
-to high, the following two writes aould be done.
-
-  write!(GPIO, 14, 2, "out")
-  write!(GPIO, 14, 1, "1")
-
-"""
-struct GPIO
-end
-
-writeOperations = [
-    Dict("dir" => "value",     "entries"=>["1", "0"])
-    Dict("dir" => "direction", "entries"=>["in", "out"])
-]
-
-readOperations = [
-    "value"
-    "direction"
-    "edge"
-]
-
-channels =[
-    "gpio112"
-    "gpio114"
-    "gpio115"
-    "gpio116"
-    "gpio14"
-    "gpio15"
-    "gpio2"
-    "gpio20"
-    "gpio22"
-    "gpio23"
-    "gpio26"
-    "gpio27"
-    "gpio3"
-    "gpio30"
-    "gpio31"
-    "gpio4"
-    "gpio44"
-    "gpio45"
-    "gpio46"
-    "gpio47"
-    "gpio48"
-    "gpio49"
-    "gpio5"
-    "gpio50"
-    "gpio51"
-    "gpio60"
-    "gpio61"
-    "gpio65"
-    "gpio66"
-    "gpio67"
-    "gpio68"
-    "gpio69"
-    "gpio7"
-]
-
-function write!(::GPIO, index::Int32, operation::Int32, entry::Bool)
-    (index <= 0 || index > length(channels)) && error("Invalid GPIO index: $index")
-    (operation <= 0 || operation > length(writeOperations)) && error("Invalid GPIO operation: $operation")
-    filename = "/sys/class/gpio/$(channels[index])/$(writeOperations[operation]["dir"])"
-
-    value = writeOperations[operation]["entries"][entry ? 1 : 2]
-    file = open(filename, "r+")
-
-    write(file, "$(value)")
-    close(file)
-    return
-end
-
-#function Base.read(::SysLED, ind::Int32)
-#    (ind < 0 || ind > length(channels)) && error("Invalid SysLEND ind: $ind")
-#    println("not yet supported")
-#    l = 0
-#    return l == "1"
-#end

test/BeagleBone/GPIO_test.jl

-include("../../src/BeagleBone/BeagleBone.jl")
-
-using Base.Test
-
-#Fixture
-device = getdev("gpio")
-gpio_state = true
-
-@testset "GPIO Tests" begin
-    @testset "Error Handling" begin
-        # Attempt to initialize faulty device
-        @test_throws ErrorException  getdev("wrong_device_name")
-
-        # Test that an exception is thrown when a faulty ID is given
-        @test_throws ErrorException write!(device, 100, 1, gpio_state)
-
-        # Test that an exception is thrown when a faulty ID is given
-        @test_throws ErrorException write!(device, 0, 1, gpio_state)
-    end
-    @testset "IO Communication" begin
-        # Instanciate all possible leds and perform 10 read/write commands
-        # with the set high/low operation (1)
-        operation = 1
-        for i = 1:10
-            for index = 1:length(channels)
-                write!(device, index, operation, gpio_state)
-            end
-            sleep(0.01)
-            #for j = 1:4
-                #val = read(device, j)
-                #@test val == gpio_state
-            #end
-            gpio_state = !gpio_state
-        end
-    end
-end