examples: example with LoRa AT command set implementation

Signed-off-by: deadprogram <ron@hybridgroup.com>

examples/lora/atcmd/sx127x.go

@@ -0,0 +1,85 @@
+//go:build featherwing
+
+package main
+
+import (
+	"strconv"
+
+	"machine"
+
+	"tinygo.org/x/drivers/lora"
+	"tinygo.org/x/drivers/sx127x"
+)
+
+const (
+	FREQ                      = 868100000
+	LORA_DEFAULT_RXTIMEOUT_MS = 1000
+	LORA_DEFAULT_TXTIMEOUT_MS = 5000
+)
+
+var (
+	// We assume LoRa Featherwing module is connected to PyBadge:
+	rstPin    = machine.D11
+	csPin     = machine.D10
+	dio0Pin   = machine.D6
+	dio1Pin   = machine.D9
+	spi       = machine.SPI0
+	loraRadio *sx127x.Device
+)
+
+// do sx127x setup here
+func setupLora() (LoraRadio, error) {
+	rstPin.Configure(machine.PinConfig{Mode: machine.PinOutput})
+	csPin.Configure(machine.PinConfig{Mode: machine.PinOutput})
+	dio0Pin.Configure(machine.PinConfig{Mode: machine.PinInputPullup})
+	dio1Pin.Configure(machine.PinConfig{Mode: machine.PinInputPullup})
+	spi.Configure(machine.SPIConfig{Frequency: 500000, Mode: 0})
+
+	loraRadio = sx127x.New(spi, csPin, rstPin)
+	loraRadio.Reset()
+
+	if state := loraRadio.DetectDevice(); !state {
+		return nil, errRadioNotFound
+	}
+
+	// Setup DIO0 interrupt Handling
+	if err := dio0Pin.SetInterrupt(machine.PinRising, dioIrqHandler); err != nil {
+		println("could not configure DIO0 pin interrupt:", err.Error())
+	}
+
+	// Setup DIO1 interrupt Handling
+	if err := dio1Pin.SetInterrupt(machine.PinRising, dioIrqHandler); err != nil {
+		println("could not configure DIO1 pin interrupt:", err.Error())
+	}
+
+	// Prepare for Lora Operation
+	loraConf := lora.Config{
+		Freq:           FREQ,
+		Bw:             lora.Bandwidth_500_0,
+		Sf:             lora.SpreadingFactor9,
+		Cr:             lora.CodingRate4_7,
+		HeaderType:     lora.HeaderExplicit,
+		Preamble:       12,
+		Iq:             lora.IQStandard,
+		Crc:            lora.CRCOn,
+		SyncWord:       lora.SyncPrivate,
+		LoraTxPowerDBm: 20,
+	}
+
+	loraRadio.LoraConfig(loraConf)
+
+	return loraRadio, nil
+}
+
+func dioIrqHandler(machine.Pin) {
+	loraRadio.HandleInterrupt()
+}
+
+func firmwareVersion() string {
+	v := loraRadio.GetVersion()
+	return "sx127x v" + strconv.Itoa(int(v))
+}
+
+func lorarx() ([]byte, error) {
+	return loraRadio.Rx(LORA_DEFAULT_RXTIMEOUT_MS)
+}