sx126x: Driver for Semtech sx126x radio modules and optional RF Switch.

This first version of the driver has been tested with STM32WL SoC,
	which embeddeds SX1262 radio on the same die.

examples/sx126x/rfswitch/lorae5.go

@@ -0,0 +1,43 @@
+//go:build lorae5
+// +build lorae5
+
+package radio
+
+/*
+/!\ LoRa-E5 module ONLY transmits through RFO_HP:
+
+	Receive: PA4=1, PA5=0
+	Transmit(high output power, SMPS mode): PA4=0, PA5=1
+
+*/
+
+import (
+	"errors"
+	"machine"
+
+	"tinygo.org/x/drivers/sx126x"
+)
+
+type CustomSwitch struct {
+}
+
+func (s CustomSwitch) InitRFSwitch() {
+	machine.PA4.Configure(machine.PinConfig{Mode: machine.PinOutput})
+	machine.PB5.Configure(machine.PinConfig{Mode: machine.PinOutput})
+}
+
+func (s CustomSwitch) SetRfSwitchMode(mode int) error {
+	switch mode {
+
+	case sx126x.RFSWITCH_RX:
+		machine.PA4.Set(true)
+		machine.PB5.Set(false)
+	case sx126x.RFSWITCH_TX_LP:
+		errors.New("RFSWITCH_TX_LP not supported ")
+	case sx126x.RFSWITCH_TX_HP:
+		machine.PA4.Set(false)
+		machine.PB5.Set(true)
+
+	}
+	return nil
+}