Added pmic configuration on nono iot 33 variant

added pmic configuration suppoort  on nano iot 33, this is enabled only when a arduino motor carrier board is attached and the realted library is used

variants/nano_33_iot/variant.cpp

@@ -167,7 +167,86 @@ extern "C" {
 
 const void* g_apTCInstances[TCC_INST_NUM+TC_INST_NUM]={ TCC0, TCC1, TCC2, TC3, TC4, TC5 } ;
 
+#if defined(__ARDUINOMOTORSHIELD__)
+#include "wiring_private.h"
+
+#define PMIC_ADDRESS  0x6B
+#define PMIC_REG01    0x01
+#define PMIC_REG05    0x05
+#define PMIC_REG07    0x07
+
+static inline void enable_battery_charging() {
+  PERIPH_WIRE.initMasterWIRE(100000);
+  PERIPH_WIRE.enableWIRE();
+  pinPeripheral(PIN_WIRE_SDA, g_APinDescription[PIN_WIRE_SDA].ulPinType);
+  pinPeripheral(PIN_WIRE_SCL, g_APinDescription[PIN_WIRE_SCL].ulPinType);
+
+  PERIPH_WIRE.startTransmissionWIRE( PMIC_ADDRESS, WIRE_WRITE_FLAG );
+  PERIPH_WIRE.sendDataMasterWIRE(PMIC_REG01);
+  PERIPH_WIRE.sendDataMasterWIRE(0x1B); // Charge Battery + Minimum System Voltage 3.5V
+  PERIPH_WIRE.prepareCommandBitsWire(WIRE_MASTER_ACT_STOP);
+
+  PERIPH_WIRE.disableWIRE();
+}
+
+static inline void disable_battery_fet(bool disabled) {
+  PERIPH_WIRE.initMasterWIRE(100000);
+  PERIPH_WIRE.enableWIRE();
+  pinPeripheral(PIN_WIRE_SDA, g_APinDescription[PIN_WIRE_SDA].ulPinType);
+  pinPeripheral(PIN_WIRE_SCL, g_APinDescription[PIN_WIRE_SCL].ulPinType);
+
+  PERIPH_WIRE.startTransmissionWIRE( PMIC_ADDRESS, WIRE_WRITE_FLAG );
+  PERIPH_WIRE.sendDataMasterWIRE(PMIC_REG07);
+  // No D+/D– detection + Safety timer not slowed by 2X during input DPM or thermal regulation +
+  // BAT fet disabled/enabled + charge and bat fault INT
+  PERIPH_WIRE.sendDataMasterWIRE(0x0B | (disabled ? 0x20 : 0x00));
+  PERIPH_WIRE.prepareCommandBitsWire(WIRE_MASTER_ACT_STOP);
+
+  PERIPH_WIRE.disableWIRE();
+}
+
+void disable_watchdog() {
+  PERIPH_WIRE.initMasterWIRE(100000);
+  PERIPH_WIRE.enableWIRE();
+  pinPeripheral(PIN_WIRE_SDA, g_APinDescription[PIN_WIRE_SDA].ulPinType);
+  pinPeripheral(PIN_WIRE_SCL, g_APinDescription[PIN_WIRE_SCL].ulPinType);
+
+  PERIPH_WIRE.startTransmissionWIRE( PMIC_ADDRESS, WIRE_WRITE_FLAG );
+  PERIPH_WIRE.sendDataMasterWIRE(PMIC_REG05);
+  PERIPH_WIRE.sendDataMasterWIRE(0x8A); // disable wahcdog
+  PERIPH_WIRE.prepareCommandBitsWire(WIRE_MASTER_ACT_STOP);
+
+  PERIPH_WIRE.disableWIRE();
+
+    int DATA = readRegister(CHARGE_TIMER_CONTROL_REGISTER);
+
+    if (DATA == -1) {
+        return 0;
+    }
+
+    return writeRegister(CHARGE_TIMER_CONTROL_REGISTER, (DATA & 0b11001110));
+}
+
+#endif
+
+
 void initVariant() {
+#if defined(__ARDUINOMOTORSHIELD__)
+  pinMode(ADC_BATTERY, OUTPUT);
+  digitalWrite(ADC_BATTERY, LOW);
+  delay(10);
+  pinMode(ADC_BATTERY, INPUT);
+  delay(100);
+
+  bool batteryPresent = analogRead(ADC_BATTERY) > 600;
+  if (batteryPresent) {
+    disable_watchdog();
+    enable_battery_charging();
+  }
+  disable_battery_fet(!batteryPresent);
+#endif
+
+
   // NINA - SPI boot
   pinMode(NINA_GPIO0, OUTPUT);
   digitalWrite(NINA_GPIO0, HIGH);
@@ -185,6 +264,8 @@ SERCOM sercom3( SERCOM3 ) ;
 SERCOM sercom4( SERCOM4 ) ;
 SERCOM sercom5( SERCOM5 ) ;
 
+
+
 Uart Serial1( &sercom5, PIN_SERIAL1_RX, PIN_SERIAL1_TX, PAD_SERIAL1_RX, PAD_SERIAL1_TX ) ;
 
 void SERCOM5_Handler()