func main() {
// get a pin by name. You could also just use the logical pin number, but this is
// more readable. On BeagleBone, USR0 is an on-board LED.
ledPin, err := hwio.GetPin("USR1")
// Generally we wouldn't expect an error, but perhaps someone is running this a
if err != nil {
fmt.Println(err)
os.Exit(1)
}
// Set the mode of the pin to output. This will return an error if, for example,
// we were trying to set an analog input to an output.
err = hwio.PinMode(ledPin, hwio.OUTPUT)
if err != nil {
fmt.Println(err)
os.Exit(1)
}
// Run the blink forever
for {
hwio.DigitalWrite(ledPin, hwio.HIGH)
hwio.Delay(1000)
hwio.DigitalWrite(ledPin, hwio.LOW)
hwio.Delay(1000)
}
}
func main() {
// Get the pins we're going to use. These are on a beaglebone.
sinPin, _ := hwio.GetPin("P9.11")
sclkPin, _ := hwio.GetPin("P9.12")
xlatPin, _ := hwio.GetPin("P9.13")
gsclkPin, _ := hwio.GetPin("P9.14")
blankPin, _ := hwio.GetPin("P9.15")
fmt.Printf("Pins are: sin=%d, sclk=%d, xlat=%d, gsclk=%d, blank=%d", sinPin, sclkPin, xlatPin, gsclkPin, blankPin)
// Make them all outputs
e := hwio.PinMode(sinPin, hwio.OUTPUT)
if e == nil {
hwio.PinMode(sclkPin, hwio.OUTPUT)
}
if e == nil {
hwio.PinMode(xlatPin, hwio.OUTPUT)
}
if e == nil {
hwio.PinMode(gsclkPin, hwio.OUTPUT)
}
if e == nil {
hwio.PinMode(blankPin, hwio.OUTPUT)
}
if e != nil {
fmt.Printf("Could not initialise pins: %s", e)
return
}
// set clocks low
hwio.DigitalWrite(sclkPin, hwio.LOW)
hwio.DigitalWrite(xlatPin, hwio.LOW)
hwio.DigitalWrite(gsclkPin, hwio.LOW)
// run GS clock in it's own space
hwio.DigitalWrite(blankPin, hwio.HIGH)
hwio.DigitalWrite(blankPin, hwio.LOW)
clockData(gsclkPin)
for b := 0; b < 4096; b++ {
writeData(uint(b), sinPin, sclkPin, xlatPin)
for j := 0; j < 10; j++ {
hwio.DigitalWrite(blankPin, hwio.HIGH)
hwio.DigitalWrite(blankPin, hwio.LOW)
clockData(gsclkPin)
}
// hwio.Delay(100)
}
// hwio.ShiftOut(dataPin, clockPin, uint(data), hwio.MSBFIRST)
}
func main() {
// Get the pins we're going to use. These are on a beaglebone.
dataPin, _ := hwio.GetPin("P8.3") // connected to pin 14
clockPin, _ := hwio.GetPin("P8.4") // connected to pin 11
storePin, _ := hwio.GetPin("P8.5") // connected to pin 12
// Make them all outputs
hwio.PinMode(dataPin, hwio.OUTPUT)
hwio.PinMode(clockPin, hwio.OUTPUT)
hwio.PinMode(storePin, hwio.OUTPUT)
data := 0
// Set the initial state of the clock and store pins to low. These both
// trigger on the rising edge.
hwio.DigitalWrite(clockPin, hwio.LOW)
hwio.DigitalWrite(storePin, hwio.LOW)
for {
// Shift out 8 bits
hwio.ShiftOut(dataPin, clockPin, uint(data), hwio.MSBFIRST)
// You can use this line instead to clock out 16 bits if you have
// two 74HC595's chained together
// hwio.ShiftOutSize(dataPin, clockPin, uint(data), hwio.MSBFIRST, 16)
// Pulse the store pin once
hwio.DigitalWrite(storePin, hwio.HIGH)
hwio.DigitalWrite(storePin, hwio.LOW)
// Poor humans cannot read binary as fast as the machine can display it
hwio.Delay(100)
data++
}
}
// val is a 12-bit int
func writeData(val uint, sinPin hwio.Pin, sclkPin hwio.Pin, xlatPin hwio.Pin) {
fmt.Printf("writing data %d\n", val)
bits := 0
mask := uint(1) << 11
for i := 0; i < 16; i++ {
v := val
for j := 0; j < 12; j++ {
if (v & mask) != 0 {
hwio.DigitalWrite(sinPin, hwio.HIGH)
} else {
hwio.DigitalWrite(sinPin, hwio.HIGH)
}
hwio.DigitalWrite(sclkPin, hwio.HIGH)
hwio.DigitalWrite(sclkPin, hwio.LOW)
v = v << 1
bits++
}
}
hwio.DigitalWrite(xlatPin, hwio.HIGH)
hwio.DigitalWrite(xlatPin, hwio.LOW)
fmt.Printf("Wrote %d bits\n", bits)
}
func clockData(gsclkPin hwio.Pin) {
for g := 0; g < 4096; g++ {
hwio.DigitalWrite(gsclkPin, hwio.HIGH)
hwio.DigitalWrite(gsclkPin, hwio.LOW)
}
}