From 1b2b8bd67b9c22544be0a6df105c50b01648a7a6 Mon Sep 17 00:00:00 2001
From: StevenCellist <47155822+StevenCellist@users.noreply.github.com>
Date: Wed, 1 May 2024 13:35:22 +0200
Subject: [PATCH] [LoRaWAN] Improve PHY behaviour, update beginABP, bugfixes
 (#1080)

* [LoRaWAN] Add getter for ToA, prevent MAC queue overflow

* [LoRaWAN] Permute arguments to beginABP

* Implement & split off checkOutputPower

* [LoRaWAN] Configure physical layer on each up/downlink

* [LoRaWAN] Remove unnecessary dynamic array

* [LoRaWAN] Improve downlink handling

* Resolve return-warnings in checkOutputPower()

* [LoRaWAN] Improve buffer definition

* [LoRaWAN] Prevent requesting repeated MAC commands

* Update keywords.txt

* [CC1101] Resolve unused variable warning

* [CC1101] Update checkOutputPower

* [SX1278] Fix variable assignment

* Update keywords.txt

* [CC1101] Added checkOutputPower override for PHY compatibility

* [LR11x0] Added checkOutputPower override for PHY compatibility

* [SX127x] Added checkOutputPower override for PHY compatibility

---------

Co-authored-by: jgromes <jan.gromes@gmail.com>
---
 .github/workflows/main.yml                    |   2 +-
 examples/LoRaWAN/LoRaWAN_ABP/configABP.h      |   6 +-
 keywords.txt                                  |   3 +-
 src/modules/CC1101/CC1101.cpp                 | 110 ++++++---
 src/modules/CC1101/CC1101.h                   |  18 ++
 src/modules/LR11x0/LR11x0.cpp                 |  36 ++-
 src/modules/LR11x0/LR11x0.h                   |  19 ++
 src/modules/SX126x/SX1261.cpp                 |  14 +-
 src/modules/SX126x/SX1261.h                   |   8 +
 src/modules/SX126x/SX1262.cpp                 |  14 +-
 src/modules/SX126x/SX1262.h                   |   8 +
 src/modules/SX126x/SX1268.cpp                 |  14 +-
 src/modules/SX126x/SX1268.h                   |   8 +
 src/modules/SX127x/SX1272.cpp                 |  31 ++-
 src/modules/SX127x/SX1272.h                   |  18 ++
 src/modules/SX127x/SX1278.cpp                 |  43 +++-
 src/modules/SX127x/SX1278.h                   |  18 ++
 src/modules/SX128x/SX128x.cpp                 |  13 +-
 src/modules/SX128x/SX128x.h                   |   8 +
 src/protocols/LoRaWAN/LoRaWAN.cpp             | 223 +++++++++--------
 src/protocols/LoRaWAN/LoRaWAN.h               | 224 +++++++++---------
 src/protocols/PhysicalLayer/PhysicalLayer.cpp |   6 +
 src/protocols/PhysicalLayer/PhysicalLayer.h   |   8 +
 23 files changed, 561 insertions(+), 291 deletions(-)

diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index e7d4cbe3f..48acb19a9 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -170,7 +170,7 @@ jobs:
             else
               # apply special flags for LoRaWAN
               if [[ ${example} =~ "LoRaWAN" ]]; then
-                flags="-DRADIOLIB_LORAWAN_DEV_ADDR=0 -DRADIOLIB_LORAWAN_NWKS_KEY=0 -DRADIOLIB_LORAWAN_SNWKSINT_KEY=0 -DRADIOLIB_LORAWAN_NWKSENC_KEY=0 -DRADIOLIB_LORAWAN_APPS_KEY=0 -DRADIOLIB_LORAWAN_APP_KEY=0 -DRADIOLIB_LORAWAN_NWK_KEY=0 -DRADIOLIB_LORAWAN_DEV_EUI=0 -DARDUINO_TTGO_LORA32_V1"
+                flags="-DRADIOLIB_LORAWAN_DEV_ADDR=0 -DRADIOLIB_LORAWAN_FNWKSINT_KEY=0 -DRADIOLIB_LORAWAN_SNWKSINT_KEY=0 -DRADIOLIB_LORAWAN_NWKSENC_KEY=0 -DRADIOLIB_LORAWAN_APPS_KEY=0 -DRADIOLIB_LORAWAN_APP_KEY=0 -DRADIOLIB_LORAWAN_NWK_KEY=0 -DRADIOLIB_LORAWAN_DEV_EUI=0 -DARDUINO_TTGO_LORA32_V1"
               fi
 
               # build sketch
diff --git a/examples/LoRaWAN/LoRaWAN_ABP/configABP.h b/examples/LoRaWAN/LoRaWAN_ABP/configABP.h
index 52e39d8e6..b9de72e7d 100644
--- a/examples/LoRaWAN/LoRaWAN_ABP/configABP.h
+++ b/examples/LoRaWAN/LoRaWAN_ABP/configABP.h
@@ -12,8 +12,8 @@ const uint32_t uplinkIntervalSeconds = 5UL * 60UL;    // minutes x seconds
 #define RADIOLIB_LORAWAN_DEV_ADDR   0x------
 #endif
 
-#ifndef RADIOLIB_LORAWAN_NWKS_KEY   // Replace with your NwkS Key 
-#define RADIOLIB_LORAWAN_NWKS_KEY   0x--, 0x--, 0x--, 0x--, 0x--, 0x--, 0x--, 0x--, 0x--, 0x--, 0x--, 0x--, 0x--, 0x--, 0x--, 0x-- 
+#ifndef RADIOLIB_LORAWAN_FNWKSINT_KEY   // Replace with your FNwkSInt Key 
+#define RADIOLIB_LORAWAN_FNWKSINT_KEY   0x--, 0x--, 0x--, 0x--, 0x--, 0x--, 0x--, 0x--, 0x--, 0x--, 0x--, 0x--, 0x--, 0x--, 0x--, 0x-- 
 #endif
 #ifndef RADIOLIB_LORAWAN_SNWKSINT_KEY   // Replace with your SNwkSInt Key 
 #define RADIOLIB_LORAWAN_SNWKSINT_KEY   0x--, 0x--, 0x--, 0x--, 0x--, 0x--, 0x--, 0x--, 0x--, 0x--, 0x--, 0x--, 0x--, 0x--, 0x--, 0x-- 
@@ -118,7 +118,7 @@ const uint8_t subBand = 0;  // For US915, change this to 2, otherwise leave on 0
 
 // copy over the keys in to the something that will not compile if incorrectly formatted
 uint32_t devAddr =        RADIOLIB_LORAWAN_DEV_ADDR;
-uint8_t NwkSKey[] =     { RADIOLIB_LORAWAN_NWKS_KEY };
+uint8_t NwkSKey[] =     { RADIOLIB_LORAWAN_FNWKSINT_KEY };
 uint8_t SNwkSIntKey[] = { RADIOLIB_LORAWAN_SNWKSINT_KEY }; // Previously sNwkSIntKey
 uint8_t NwkSEncKey[] =  { RADIOLIB_LORAWAN_NWKSENC_KEY }; // Previously fNwkSIntKey
 uint8_t AppSKey[] =     { RADIOLIB_LORAWAN_APPS_KEY };
diff --git a/keywords.txt b/keywords.txt
index d160e7820..5fbbcbb37 100644
--- a/keywords.txt
+++ b/keywords.txt
@@ -127,6 +127,7 @@ setCodingRate	KEYWORD2
 setFrequency	KEYWORD2
 setSyncWord	KEYWORD2
 setOutputPower	KEYWORD2
+checkOutputPower	KEYWORD2
 setCurrentLimit	KEYWORD2
 setPreambleLength	KEYWORD2
 setGain	KEYWORD2
@@ -328,10 +329,10 @@ timeUntilUplink	KEYWORD2
 setDwellTime	KEYWORD2
 maxPayloadDwellTime	KEYWORD2
 setTxPower	KEYWORD2
-setCSMA	KEYWORD2
 getMacLinkCheckAns	KEYWORD2
 getMacDeviceTimeAns	KEYWORD2
 getDevAddr	KEYWORD2
+getLastToA	KEYWORD2
 
 #######################################
 # Constants (LITERAL1)
diff --git a/src/modules/CC1101/CC1101.cpp b/src/modules/CC1101/CC1101.cpp
index 5d8f963b0..1da68a02d 100644
--- a/src/modules/CC1101/CC1101.cpp
+++ b/src/modules/CC1101/CC1101.cpp
@@ -560,6 +560,62 @@ int16_t CC1101::getFrequencyDeviation(float *freqDev) {
 }
 
 int16_t CC1101::setOutputPower(int8_t pwr) {
+  // check if power value is configurable
+  uint8_t powerRaw = 0;
+  int16_t state = checkOutputPower(pwr, NULL, &powerRaw);
+  RADIOLIB_ASSERT(state);
+
+  // store the value
+  this->power = pwr;
+
+  if(this->modulation == RADIOLIB_CC1101_MOD_FORMAT_ASK_OOK){
+    // Amplitude modulation:
+    // PA_TABLE[0] is the power to be used when transmitting a 0  (no power)
+    // PA_TABLE[1] is the power to be used when transmitting a 1  (full power)
+
+    uint8_t paValues[2] = {0x00, powerRaw};
+    SPIwriteRegisterBurst(RADIOLIB_CC1101_REG_PATABLE, paValues, 2);
+    return(RADIOLIB_ERR_NONE);
+
+  } else {
+    // Freq modulation:
+    // PA_TABLE[0] is the power to be used when transmitting.
+    return(SPIsetRegValue(RADIOLIB_CC1101_REG_PATABLE, powerRaw));
+  }
+}
+
+int16_t CC1101::checkOutputPower(int8_t power, int8_t* clipped) {
+  return(checkOutputPower(power, clipped, NULL));
+}
+
+int16_t CC1101::checkOutputPower(int8_t power, int8_t* clipped, uint8_t* raw) {
+  constexpr int8_t allowedPwrs[8] = { -30, -20, -15, -10, 0, 5, 7, 10 };
+
+  if(clipped) {
+    if(power <= -30) {
+      *clipped = -30;
+    } else if(power >= 10) {
+      *clipped = 10;
+    } else {
+      for(int i = 0; i < 8; i++) {
+        if(allowedPwrs[i] > power) {
+          break;
+        }
+        *clipped = allowedPwrs[i];
+      }
+    }
+  }
+
+  // if just a check occurs (and not requesting the raw power value), return now
+  if(!raw) {
+    for(int i = 0; i < 8; i++) {
+      if(allowedPwrs[i] == power) {
+        return(RADIOLIB_ERR_NONE);
+      }
+    }
+    return(RADIOLIB_ERR_INVALID_OUTPUT_POWER);
+  }
+
   // round to the known frequency settings
   uint8_t f;
   if(this->frequency < 374.0) {
@@ -586,53 +642,35 @@ int16_t CC1101::setOutputPower(int8_t pwr) {
                            {0xCB, 0xC8, 0xCB, 0xC7},
                            {0xC2, 0xC0, 0xC2, 0xC0}};
 
-  uint8_t powerRaw;
-  switch(pwr) {
-    case -30:
-      powerRaw = paTable[0][f];
+  switch(power) {
+    case allowedPwrs[0]:  // -30
+      *raw = paTable[0][f];
       break;
-    case -20:
-      powerRaw = paTable[1][f];
+    case allowedPwrs[1]:  // -20
+      *raw = paTable[1][f];
       break;
-    case -15:
-      powerRaw = paTable[2][f];
+    case allowedPwrs[2]:  // -15
+      *raw = paTable[2][f];
       break;
-    case -10:
-      powerRaw = paTable[3][f];
+    case allowedPwrs[3]:  // -10
+      *raw = paTable[3][f];
       break;
-    case 0:
-      powerRaw = paTable[4][f];
+    case allowedPwrs[4]:  // 0
+      *raw = paTable[4][f];
       break;
-    case 5:
-      powerRaw = paTable[5][f];
+    case allowedPwrs[5]:  // 5
+      *raw = paTable[5][f];
       break;
-    case 7:
-      powerRaw = paTable[6][f];
+    case allowedPwrs[6]:  // 7
+      *raw = paTable[6][f];
       break;
-    case 10:
-      powerRaw = paTable[7][f];
+    case allowedPwrs[7]:  // 10
+      *raw = paTable[7][f];
       break;
     default:
       return(RADIOLIB_ERR_INVALID_OUTPUT_POWER);
   }
-
-  // store the value
-  this->power = pwr;
-
-  if(this->modulation == RADIOLIB_CC1101_MOD_FORMAT_ASK_OOK){
-    // Amplitude modulation:
-    // PA_TABLE[0] is the power to be used when transmitting a 0  (no power)
-    // PA_TABLE[1] is the power to be used when transmitting a 1  (full power)
-
-    uint8_t paValues[2] = {0x00, powerRaw};
-    SPIwriteRegisterBurst(RADIOLIB_CC1101_REG_PATABLE, paValues, 2);
-    return(RADIOLIB_ERR_NONE);
-
-  } else {
-    // Freq modulation:
-    // PA_TABLE[0] is the power to be used when transmitting.
-    return(SPIsetRegValue(RADIOLIB_CC1101_REG_PATABLE, powerRaw));
-  }
+  return(RADIOLIB_ERR_NONE);
 }
 
 int16_t CC1101::setSyncWord(uint8_t* syncWord, uint8_t len, uint8_t maxErrBits, bool requireCarrierSense) {
diff --git a/src/modules/CC1101/CC1101.h b/src/modules/CC1101/CC1101.h
index 3619d2184..237e1dcf2 100644
--- a/src/modules/CC1101/CC1101.h
+++ b/src/modules/CC1101/CC1101.h
@@ -774,6 +774,24 @@ class CC1101: public PhysicalLayer {
     */
     int16_t setOutputPower(int8_t pwr);
 
+    /*!
+      \brief Check if output power is configurable.
+      This method is needed for compatibility with PhysicalLayer::checkOutputPower.
+      \param power Output power in dBm.
+      \param clipped Clipped output power value to what is possible within the module's range.
+      \returns \ref status_codes
+    */
+    int16_t checkOutputPower(int8_t power, int8_t* clipped) override;
+
+    /*!
+      \brief Check if output power is configurable.
+      \param power Output power in dBm.
+      \param clipped Clipped output power value to what is possible within the module's range.
+      \param raw Raw internal value.
+      \returns \ref status_codes
+    */
+    int16_t checkOutputPower(int8_t power, int8_t* clipped, uint8_t* raw);
+
     /*!
       \brief Sets 16-bit sync word as a two byte value.
       \param syncH MSB of the sync word.
diff --git a/src/modules/LR11x0/LR11x0.cpp b/src/modules/LR11x0/LR11x0.cpp
index b44c1bb07..c9244bb89 100644
--- a/src/modules/LR11x0/LR11x0.cpp
+++ b/src/modules/LR11x0/LR11x0.cpp
@@ -593,22 +593,17 @@ int16_t LR11x0::setOutputPower(int8_t power) {
 }
 
 int16_t LR11x0::setOutputPower(int8_t power, bool forceHighPower) {
+  // check if power value is configurable
+  int16_t state = checkOutputPower(power, NULL, forceHighPower);
+  RADIOLIB_ASSERT(state);
+
   // determine whether to use HP or LP PA and check range accordingly
   bool useHp = forceHighPower || (power > 14);
-  if(useHp) {
-    RADIOLIB_CHECK_RANGE(power, -9, 22, RADIOLIB_ERR_INVALID_OUTPUT_POWER);
-    useHp = true;
-  
-  } else {
-    RADIOLIB_CHECK_RANGE(power, -17, 14, RADIOLIB_ERR_INVALID_OUTPUT_POWER);
-    useHp = false;
   
-  }
-
   // TODO how and when to configure OCP?
 
   // update PA config - always use VBAT for high-power PA
-  int16_t state = setPaConfig((uint8_t)useHp, (uint8_t)useHp, 0x04, 0x07);
+  state = setPaConfig((uint8_t)useHp, (uint8_t)useHp, 0x04, 0x07);
   RADIOLIB_ASSERT(state);
 
   // set output power
@@ -616,6 +611,27 @@ int16_t LR11x0::setOutputPower(int8_t power, bool forceHighPower) {
   return(state);
 }
 
+int16_t LR11x0::checkOutputPower(int8_t power, int8_t* clipped) {
+  return(checkOutputPower(power, clipped, false));
+}
+
+int16_t LR11x0::checkOutputPower(int8_t power, int8_t* clipped, bool forceHighPower) {
+  if(forceHighPower || (power > 14)) {
+    if(clipped) {
+      *clipped = RADIOLIB_MAX(-9, RADIOLIB_MIN(22, power));
+    }
+    RADIOLIB_CHECK_RANGE(power, -9, 22, RADIOLIB_ERR_INVALID_OUTPUT_POWER);
+  
+  } else {
+    if(clipped) {
+      *clipped = RADIOLIB_MAX(-17, RADIOLIB_MIN(14, power));
+    }
+    RADIOLIB_CHECK_RANGE(power, -17, 14, RADIOLIB_ERR_INVALID_OUTPUT_POWER);
+  
+  }
+  return(RADIOLIB_ERR_NONE);
+}
+
 int16_t LR11x0::setBandwidth(float bw) {
   // check active modem
   uint8_t type = RADIOLIB_LR11X0_PACKET_TYPE_NONE;
diff --git a/src/modules/LR11x0/LR11x0.h b/src/modules/LR11x0/LR11x0.h
index cdee10e53..3a100e637 100644
--- a/src/modules/LR11x0/LR11x0.h
+++ b/src/modules/LR11x0/LR11x0.h
@@ -802,6 +802,25 @@ class LR11x0: public PhysicalLayer {
     */
     int16_t setOutputPower(int8_t power, bool forceHighPower);
 
+    /*!
+      \brief Check if output power is configurable.
+      This method is needed for compatibility with PhysicalLayer::checkOutputPower.
+      \param power Output power in dBm, PA will be determined automatically.
+      \param clipped Clipped output power value to what is possible within the module's range.
+      \returns \ref status_codes
+    */
+    int16_t checkOutputPower(int8_t power, int8_t* clipped) override;
+
+    /*!
+      \brief Check if output power is configurable.
+      \param power Output power in dBm.
+      \param clipped Clipped output power value to what is possible within the module's range.
+      \param forceHighPower Force using the high-power PA. If set to false, PA will be determined automatically
+      based on configured output power, preferring the low-power PA. If set to true, only high-power PA will be used.
+      \returns \ref status_codes
+    */
+    int16_t checkOutputPower(int8_t power, int8_t* clipped, bool forceHighPower);
+
     /*!
       \brief Sets LoRa bandwidth. Allowed values are 62.5, 125.0, 250.0 and 500.0 kHz.
       \param bw LoRa bandwidth to be set in kHz.
diff --git a/src/modules/SX126x/SX1261.cpp b/src/modules/SX126x/SX1261.cpp
index cabe2b579..d6a90c342 100644
--- a/src/modules/SX126x/SX1261.cpp
+++ b/src/modules/SX126x/SX1261.cpp
@@ -6,11 +6,13 @@ SX1261::SX1261(Module* mod): SX1262(mod) {
 }
 
 int16_t SX1261::setOutputPower(int8_t power) {
-  RADIOLIB_CHECK_RANGE(power, -17, 14, RADIOLIB_ERR_INVALID_OUTPUT_POWER);
+  // check if power value is configurable
+  int16_t state = checkOutputPower(power, NULL);
+  RADIOLIB_ASSERT(state);
 
   // get current OCP configuration
   uint8_t ocp = 0;
-  int16_t state = readRegister(RADIOLIB_SX126X_REG_OCP_CONFIGURATION, &ocp, 1);
+  state = readRegister(RADIOLIB_SX126X_REG_OCP_CONFIGURATION, &ocp, 1);
   RADIOLIB_ASSERT(state);
 
   // set PA config
@@ -25,4 +27,12 @@ int16_t SX1261::setOutputPower(int8_t power) {
   return(writeRegister(RADIOLIB_SX126X_REG_OCP_CONFIGURATION, &ocp, 1));
 }
 
+int16_t SX1261::checkOutputPower(int8_t power, int8_t* clipped) {
+  if(clipped) {
+    *clipped = RADIOLIB_MAX(-17, RADIOLIB_MIN(14, power));
+  }
+  RADIOLIB_CHECK_RANGE(power, -17, 14, RADIOLIB_ERR_INVALID_OUTPUT_POWER);
+  return(RADIOLIB_ERR_NONE);
+}
+
 #endif
diff --git a/src/modules/SX126x/SX1261.h b/src/modules/SX126x/SX1261.h
index 01375d558..6f4011599 100644
--- a/src/modules/SX126x/SX1261.h
+++ b/src/modules/SX126x/SX1261.h
@@ -34,6 +34,14 @@ class SX1261 : public SX1262 {
     */
     int16_t setOutputPower(int8_t power);
 
+    /*!
+      \brief Check if output power is configurable.
+      \param power Output power in dBm.
+      \param clipped Clipped output power value to what is possible within the module's range.
+      \returns \ref status_codes
+    */
+    int16_t checkOutputPower(int8_t power, int8_t* clipped);
+
 #if !RADIOLIB_GODMODE
   private:
 #endif
diff --git a/src/modules/SX126x/SX1262.cpp b/src/modules/SX126x/SX1262.cpp
index 036cba0ad..232ad6380 100644
--- a/src/modules/SX126x/SX1262.cpp
+++ b/src/modules/SX126x/SX1262.cpp
@@ -98,11 +98,13 @@ int16_t SX1262::setFrequency(float freq, bool calibrate) {
 }
 
 int16_t SX1262::setOutputPower(int8_t power) {
-  RADIOLIB_CHECK_RANGE(power, -9, 22, RADIOLIB_ERR_INVALID_OUTPUT_POWER);
+  // check if power value is configurable
+  int16_t state = checkOutputPower(power, NULL);
+  RADIOLIB_ASSERT(state);
 
   // get current OCP configuration
   uint8_t ocp = 0;
-  int16_t state = readRegister(RADIOLIB_SX126X_REG_OCP_CONFIGURATION, &ocp, 1);
+  state = readRegister(RADIOLIB_SX126X_REG_OCP_CONFIGURATION, &ocp, 1);
   RADIOLIB_ASSERT(state);
 
   // set PA config
@@ -117,4 +119,12 @@ int16_t SX1262::setOutputPower(int8_t power) {
   return(writeRegister(RADIOLIB_SX126X_REG_OCP_CONFIGURATION, &ocp, 1));
 }
 
+int16_t SX1262::checkOutputPower(int8_t power, int8_t* clipped) {
+  if(clipped) {
+    *clipped = RADIOLIB_MAX(-9, RADIOLIB_MIN(22, power));
+  }
+  RADIOLIB_CHECK_RANGE(power, -9, 22, RADIOLIB_ERR_INVALID_OUTPUT_POWER);
+  return(RADIOLIB_ERR_NONE);
+}
+
 #endif
diff --git a/src/modules/SX126x/SX1262.h b/src/modules/SX126x/SX1262.h
index f47b1a813..ebe8652a5 100644
--- a/src/modules/SX126x/SX1262.h
+++ b/src/modules/SX126x/SX1262.h
@@ -87,6 +87,14 @@ class SX1262: public SX126x {
     */
     virtual int16_t setOutputPower(int8_t power);
 
+    /*!
+      \brief Check if output power is configurable.
+      \param power Output power in dBm.
+      \param clipped Clipped output power value to what is possible within the module's range.
+      \returns \ref status_codes
+    */
+    int16_t checkOutputPower(int8_t power, int8_t* clipped);
+
 #if !RADIOLIB_GODMODE
   private:
 #endif
diff --git a/src/modules/SX126x/SX1268.cpp b/src/modules/SX126x/SX1268.cpp
index 1b63c4d06..c50baaf16 100644
--- a/src/modules/SX126x/SX1268.cpp
+++ b/src/modules/SX126x/SX1268.cpp
@@ -93,11 +93,13 @@ int16_t SX1268::setFrequency(float freq, bool calibrate) {
 }
 
 int16_t SX1268::setOutputPower(int8_t power) {
-  RADIOLIB_CHECK_RANGE(power, -9, 22, RADIOLIB_ERR_INVALID_OUTPUT_POWER);
+  // check if power value is configurable
+  int16_t state = checkOutputPower(power, NULL);
+  RADIOLIB_ASSERT(state);
 
   // get current OCP configuration
   uint8_t ocp = 0;
-  int16_t state = readRegister(RADIOLIB_SX126X_REG_OCP_CONFIGURATION, &ocp, 1);
+  state = readRegister(RADIOLIB_SX126X_REG_OCP_CONFIGURATION, &ocp, 1);
   RADIOLIB_ASSERT(state);
 
   // set PA config
@@ -112,4 +114,12 @@ int16_t SX1268::setOutputPower(int8_t power) {
   return(writeRegister(RADIOLIB_SX126X_REG_OCP_CONFIGURATION, &ocp, 1));
 }
 
+int16_t SX1268::checkOutputPower(int8_t power, int8_t* clipped) {
+  if(clipped) {
+    *clipped = RADIOLIB_MAX(-9, RADIOLIB_MIN(22, power));
+  }
+  RADIOLIB_CHECK_RANGE(power, -9, 22, RADIOLIB_ERR_INVALID_OUTPUT_POWER);
+  return(RADIOLIB_ERR_NONE);
+}
+
 #endif
diff --git a/src/modules/SX126x/SX1268.h b/src/modules/SX126x/SX1268.h
index 04edba39f..d6f0415e7 100644
--- a/src/modules/SX126x/SX1268.h
+++ b/src/modules/SX126x/SX1268.h
@@ -85,6 +85,14 @@ class SX1268: public SX126x {
     */
     int16_t setOutputPower(int8_t power);
 
+    /*!
+      \brief Check if output power is configurable.
+      \param power Output power in dBm.
+      \param clipped Clipped output power value to what is possible within the module's range.
+      \returns \ref status_codes
+    */
+    int16_t checkOutputPower(int8_t power, int8_t* clipped);
+
 #if !RADIOLIB_GODMODE
   private:
 #endif
diff --git a/src/modules/SX127x/SX1272.cpp b/src/modules/SX127x/SX1272.cpp
index 003a1cc20..6e8b6c0bf 100644
--- a/src/modules/SX127x/SX1272.cpp
+++ b/src/modules/SX127x/SX1272.cpp
@@ -280,15 +280,12 @@ int16_t SX1272::setOutputPower(int8_t power) {
 }
 
 int16_t SX1272::setOutputPower(int8_t power, bool useRfo) {
-  // check allowed power range
-  if(useRfo) {
-    RADIOLIB_CHECK_RANGE(power, -1, 14, RADIOLIB_ERR_INVALID_OUTPUT_POWER);
-  } else {
-    RADIOLIB_CHECK_RANGE(power, 2, 20, RADIOLIB_ERR_INVALID_OUTPUT_POWER);
-  }
+  // check if power value is configurable
+  int16_t state = checkOutputPower(power, NULL, useRfo);
+  RADIOLIB_ASSERT(state);
 
   // set mode to standby
-  int16_t state = SX127x::standby();
+  state = SX127x::standby();
   Module* mod = this->getMod();
 
   if(useRfo) {
@@ -317,6 +314,26 @@ int16_t SX1272::setOutputPower(int8_t power, bool useRfo) {
   return(state);
 }
 
+int16_t SX1272::checkOutputPower(int8_t power, int8_t* clipped) {
+  return(checkOutputPower(power, clipped, false));
+}
+
+int16_t SX1272::checkOutputPower(int8_t power, int8_t* clipped, bool useRfo) {
+  // check allowed power range
+  if(useRfo) {
+    if(clipped) {
+      *clipped = RADIOLIB_MAX(-1, RADIOLIB_MIN(14, power));
+    }
+    RADIOLIB_CHECK_RANGE(power, -1, 14, RADIOLIB_ERR_INVALID_OUTPUT_POWER);
+  } else {
+    if(clipped) {
+      *clipped = RADIOLIB_MAX(2, RADIOLIB_MIN(20, power));
+    }
+    RADIOLIB_CHECK_RANGE(power, 2, 20, RADIOLIB_ERR_INVALID_OUTPUT_POWER);
+  }
+  return(RADIOLIB_ERR_NONE);
+}
+
 int16_t SX1272::setGain(uint8_t gain) {
   // check allowed range
   if(gain > 6) {
diff --git a/src/modules/SX127x/SX1272.h b/src/modules/SX127x/SX1272.h
index 37e468ee0..0f9a17171 100644
--- a/src/modules/SX127x/SX1272.h
+++ b/src/modules/SX127x/SX1272.h
@@ -206,6 +206,24 @@ class SX1272: public SX127x {
     */
     int16_t setOutputPower(int8_t power, bool useRfo);
 
+    /*!
+      \brief Check if output power is configurable.
+      This method is needed for compatibility with PhysicalLayer::checkOutputPower.
+      \param power Output power in dBm, assumes PA_BOOST pin.
+      \param clipped Clipped output power value to what is possible within the module's range.
+      \returns \ref status_codes
+    */
+    int16_t checkOutputPower(int8_t power, int8_t* clipped) override;
+
+    /*!
+      \brief Check if output power is configurable.
+      \param power Output power in dBm.
+      \param clipped Clipped output power value to what is possible within the module's range.
+      \param useRfo Whether to use the RFO (true) or the PA_BOOST (false) pin for the RF output.
+      \returns \ref status_codes
+    */
+    int16_t checkOutputPower(int8_t power, int8_t* clipped, bool useRfo);
+
     /*!
       \brief Sets gain of receiver LNA (low-noise amplifier). Can be set to any integer in range 1 to 6 where 1 is the highest gain.
       Set to 0 to enable automatic gain control (recommended).
diff --git a/src/modules/SX127x/SX1278.cpp b/src/modules/SX127x/SX1278.cpp
index 22c243038..78251d245 100644
--- a/src/modules/SX127x/SX1278.cpp
+++ b/src/modules/SX127x/SX1278.cpp
@@ -294,19 +294,12 @@ int16_t SX1278::setOutputPower(int8_t power) {
 }
 
 int16_t SX1278::setOutputPower(int8_t power, bool useRfo) {
-  // check allowed power range
-  if(useRfo) {
-    // RFO output
-    RADIOLIB_CHECK_RANGE(power, -3, 15, RADIOLIB_ERR_INVALID_OUTPUT_POWER);
-  } else {
-    // PA_BOOST output, check high-power operation
-    if(power != 20) {
-      RADIOLIB_CHECK_RANGE(power, 2, 17, RADIOLIB_ERR_INVALID_OUTPUT_POWER);
-    }
-  }
+  // check if power value is configurable
+  int16_t state = checkOutputPower(power, NULL, useRfo);
+  RADIOLIB_ASSERT(state);
 
   // set mode to standby
-  int16_t state = SX127x::standby();
+  state = SX127x::standby();
   Module* mod = this->getMod();
 
   if(useRfo) {
@@ -342,6 +335,34 @@ int16_t SX1278::setOutputPower(int8_t power, bool useRfo) {
   return(state);
 }
 
+int16_t SX1278::checkOutputPower(int8_t power, int8_t* clipped) {
+  return(checkOutputPower(power, clipped, false));
+}
+
+int16_t SX1278::checkOutputPower(int8_t power, int8_t* clipped, bool useRfo) {
+  // check allowed power range
+  if(useRfo) {
+    // RFO output
+    if(clipped) {
+      *clipped = RADIOLIB_MAX(-3, RADIOLIB_MIN(15, power));
+    }
+    RADIOLIB_CHECK_RANGE(power, -3, 15, RADIOLIB_ERR_INVALID_OUTPUT_POWER);
+  } else {
+    // PA_BOOST output, check high-power operation
+    if(clipped) {
+      if(power != 20) {
+        *clipped = RADIOLIB_MAX(2, RADIOLIB_MIN(17, power));
+      } else {
+        *clipped = 20;
+      }
+    }
+    if(power != 20) {
+      RADIOLIB_CHECK_RANGE(power, 2, 17, RADIOLIB_ERR_INVALID_OUTPUT_POWER);
+    }
+  }
+  return(RADIOLIB_ERR_NONE);
+}
+
 int16_t SX1278::setGain(uint8_t gain) {
   // check allowed range
   if(gain > 6) {
diff --git a/src/modules/SX127x/SX1278.h b/src/modules/SX127x/SX1278.h
index 371b16601..a54623a9a 100644
--- a/src/modules/SX127x/SX1278.h
+++ b/src/modules/SX127x/SX1278.h
@@ -218,6 +218,24 @@ class SX1278: public SX127x {
     */
     int16_t setOutputPower(int8_t power, bool useRfo);
 
+    /*!
+      \brief Check if output power is configurable.
+      This method is needed for compatibility with PhysicalLayer::checkOutputPower.
+      \param power Output power in dBm, assumes PA_BOOST pin.
+      \param clipped Clipped output power value to what is possible within the module's range.
+      \returns \ref status_codes
+    */
+    int16_t checkOutputPower(int8_t power, int8_t* clipped) override;
+
+    /*!
+      \brief Check if output power is configurable.
+      \param power Output power in dBm.
+      \param clipped Clipped output power value to what is possible within the module's range.
+      \param useRfo Whether to use the RFO (true) or the PA_BOOST (false) pin for the RF output.
+      \returns \ref status_codes
+    */
+    int16_t checkOutputPower(int8_t power, int8_t* clipped, bool useRfo);
+
     /*!
       \brief Sets gain of receiver LNA (low-noise amplifier). Can be set to any integer in range 1 to 6 where 1 is the highest gain.
       Set to 0 to enable automatic gain control (recommended).
diff --git a/src/modules/SX128x/SX128x.cpp b/src/modules/SX128x/SX128x.cpp
index 4d79c4ef3..00f5b5e28 100644
--- a/src/modules/SX128x/SX128x.cpp
+++ b/src/modules/SX128x/SX128x.cpp
@@ -765,11 +765,22 @@ int16_t SX128x::setCodingRate(uint8_t cr, bool longInterleaving) {
 }
 
 int16_t SX128x::setOutputPower(int8_t pwr) {
-  RADIOLIB_CHECK_RANGE(pwr, -18, 13, RADIOLIB_ERR_INVALID_OUTPUT_POWER);
+  // check if power value is configurable
+  int16_t state = checkOutputPower(power, NULL);
+  RADIOLIB_ASSERT(state);
+
   this->power = pwr + 18;
   return(setTxParams(this->power));
 }
 
+int16_t SX128x::checkOutputPower(int8_t power, int8_t* clipped) {
+  if(clipped) {
+    *clipped = RADIOLIB_MAX(-18, RADIOLIB_MIN(13, power));
+  }
+  RADIOLIB_CHECK_RANGE(power, -18, 13, RADIOLIB_ERR_INVALID_OUTPUT_POWER);
+  return(RADIOLIB_ERR_NONE);
+}
+
 int16_t SX128x::setPreambleLength(uint32_t preambleLength) {
   uint8_t modem = getPacketType();
   if((modem == RADIOLIB_SX128X_PACKET_TYPE_LORA) || (modem == RADIOLIB_SX128X_PACKET_TYPE_RANGING)) {
diff --git a/src/modules/SX128x/SX128x.h b/src/modules/SX128x/SX128x.h
index 8c8d30cd6..80618d71f 100644
--- a/src/modules/SX128x/SX128x.h
+++ b/src/modules/SX128x/SX128x.h
@@ -608,6 +608,14 @@ class SX128x: public PhysicalLayer {
     */
     int16_t setOutputPower(int8_t pwr);
 
+    /*!
+      \brief Check if output power is configurable.
+      \param power Output power in dBm.
+      \param clipped Clipped output power value to what is possible within the module's range.
+      \returns \ref status_codes
+    */
+    int16_t checkOutputPower(int8_t power, int8_t* clipped);
+
     /*!
       \brief Sets preamble length for currently active modem. Allowed values range from 1 to 65535.
       \param preambleLength Preamble length to be set in symbols (LoRa) or bits (FSK/BLE/FLRC).
diff --git a/src/protocols/LoRaWAN/LoRaWAN.cpp b/src/protocols/LoRaWAN/LoRaWAN.cpp
index 3922f1456..03d2a7f07 100644
--- a/src/protocols/LoRaWAN/LoRaWAN.cpp
+++ b/src/protocols/LoRaWAN/LoRaWAN.cpp
@@ -241,9 +241,6 @@ int16_t LoRaWANNode::restore(uint16_t checkSum, uint16_t lwMode, uint8_t lwClass
   // copy uplink MAC command queue back in place
   memcpy(&this->commandsUp, &this->bufferSession[RADIOLIB_LORAWAN_SESSION_MAC_QUEUE_UL], sizeof(LoRaWANMacCommandQueue_t));
 
-  state = this->setPhyProperties();
-  RADIOLIB_ASSERT(state);
-
   // full session is restored, so set joined flag to whichever mode is restored
   this->activeMode = LoRaWANNode::ntoh<uint16_t>(&this->bufferNonces[RADIOLIB_LORAWAN_NONCES_MODE]);
 
@@ -498,16 +495,12 @@ int16_t LoRaWANNode::beginOTAA(uint64_t joinEUI, uint64_t devEUI, uint8_t* nwkKe
   // setup all MAC properties to default values
   this->beginCommon(joinDr);
 
-  // set the physical layer configuration
-  state = this->setPhyProperties();
-  RADIOLIB_ASSERT(state);
-
   // select a random pair of Tx/Rx channels
   state = this->selectChannels();
   RADIOLIB_ASSERT(state);
 
-  // configure for uplink with default configuration
-  state = this->configureChannel(RADIOLIB_LORAWAN_CHANNEL_DIR_UPLINK);
+  // set the physical layer configuration for uplink
+  state = this->setPhyProperties(RADIOLIB_LORAWAN_CHANNEL_DIR_UPLINK);
   RADIOLIB_ASSERT(state);
 
   // copy devNonce currently in use
@@ -732,7 +725,7 @@ int16_t LoRaWANNode::beginOTAA(uint64_t joinEUI, uint64_t devEUI, uint8_t* nwkKe
   return(RADIOLIB_ERR_NONE);
 }
 
-int16_t LoRaWANNode::beginABP(uint32_t addr, uint8_t* nwkSKey, uint8_t* appSKey, uint8_t* fNwkSIntKey, uint8_t* sNwkSIntKey, bool force, uint8_t initialDr) {
+int16_t LoRaWANNode::beginABP(uint32_t addr, uint8_t* fNwkSIntKey, uint8_t* sNwkSIntKey, uint8_t* nwkSEncKey, uint8_t* appSKey, bool force, uint8_t initialDr) {
   // if not forced and already joined, don't do anything
   if(!force && this->isJoined()) {
     RADIOLIB_DEBUG_PROTOCOL_PRINTLN("beginABP(): Did not rejoin: session already active");
@@ -744,7 +737,7 @@ int16_t LoRaWANNode::beginABP(uint32_t addr, uint8_t* nwkSKey, uint8_t* appSKey,
   // check if we actually need to restart from a clean session
   uint16_t checkSum = 0;
   checkSum ^= LoRaWANNode::checkSum16(reinterpret_cast<uint8_t*>(&addr), 4);
-  checkSum ^= LoRaWANNode::checkSum16(nwkSKey, 16);
+  checkSum ^= LoRaWANNode::checkSum16(nwkSEncKey, 16);
   checkSum ^= LoRaWANNode::checkSum16(appSKey, 16);
   if(fNwkSIntKey) { checkSum ^= LoRaWANNode::checkSum16(fNwkSIntKey, 16); }
   if(sNwkSIntKey) { checkSum ^= LoRaWANNode::checkSum16(sNwkSIntKey, 16); }
@@ -763,12 +756,12 @@ int16_t LoRaWANNode::beginABP(uint32_t addr, uint8_t* nwkSKey, uint8_t* appSKey,
 
   this->devAddr = addr;
   memcpy(this->appSKey, appSKey, RADIOLIB_AES128_KEY_SIZE);
-  memcpy(this->nwkSEncKey, nwkSKey, RADIOLIB_AES128_KEY_SIZE);
+  memcpy(this->nwkSEncKey, nwkSEncKey, RADIOLIB_AES128_KEY_SIZE);
   if(fNwkSIntKey) {
     this->rev = 1;
     memcpy(this->fNwkSIntKey, fNwkSIntKey, RADIOLIB_AES128_KEY_SIZE);
   } else {
-    memcpy(this->fNwkSIntKey, nwkSKey, RADIOLIB_AES128_KEY_SIZE);
+    memcpy(this->fNwkSIntKey, nwkSEncKey, RADIOLIB_AES128_KEY_SIZE);
   }
   if(sNwkSIntKey) {
     memcpy(this->sNwkSIntKey, sNwkSIntKey, RADIOLIB_AES128_KEY_SIZE);
@@ -784,10 +777,6 @@ int16_t LoRaWANNode::beginABP(uint32_t addr, uint8_t* nwkSKey, uint8_t* appSKey,
   // setup all MAC properties to default values
   this->beginCommon(initialDr);
 
-  // set the physical layer configuration
-  state = this->setPhyProperties();
-  RADIOLIB_ASSERT(state);
-
   // reset all frame counters
   this->fcntUp = 0;
   this->aFcntDown = 0;
@@ -970,9 +959,9 @@ int16_t LoRaWANNode::uplink(uint8_t* data, size_t len, uint8_t port, bool isConf
     }
   }
 
-  // configure for uplink
+  // set the physical layer configuration for uplink
   this->selectChannels();
-  state = this->configureChannel(RADIOLIB_LORAWAN_CHANNEL_DIR_UPLINK);
+  state = this->setPhyProperties(RADIOLIB_LORAWAN_CHANNEL_DIR_UPLINK);
   RADIOLIB_ASSERT(state);
 
   // if dwell time is imposed, calculated expected time on air and cancel if exceeds
@@ -1019,12 +1008,8 @@ int16_t LoRaWANNode::uplink(uint8_t* data, size_t len, uint8_t port, bool isConf
 
   // check if we have some MAC commands to append
   if(foptsLen > 0) {
-    #if RADIOLIB_STATIC_ONLY
     // assume maximum possible buffer size
     uint8_t foptsBuff[RADIOLIB_LORAWAN_FHDR_FOPTS_MAX_LEN];
-    #else
-    uint8_t* foptsBuff = new uint8_t[foptsLen];
-    #endif
     uint8_t* foptsPtr = foptsBuff;
 
     // append all MAC replies into fopts buffer
@@ -1052,9 +1037,6 @@ int16_t LoRaWANNode::uplink(uint8_t* data, size_t len, uint8_t port, bool isConf
     // encrypt it
     processAES(foptsBuff, foptsLen, this->nwkSEncKey, &uplinkMsg[RADIOLIB_LORAWAN_FHDR_FOPTS_POS], this->fcntUp, RADIOLIB_LORAWAN_CHANNEL_DIR_UPLINK, 0x01, true);
     
-    #if !RADIOLIB_STATIC_ONLY
-    delete[] foptsBuff;
-    #endif
   }
 
   // set the port
@@ -1146,30 +1128,28 @@ int16_t LoRaWANNode::uplink(uint8_t* data, size_t len, uint8_t port, bool isConf
 
 int16_t LoRaWANNode::downlinkCommon() {
   Module* mod = this->phyLayer->getMod();
-  const RadioLibTime_t scanGuard = 10;
+
+  // according to the spec, the Rx window must be at least enough time to effectively detect a preamble
+  // but we pad it a bit on both sides (start and end) to make sure it is wide enough
+  const RadioLibTime_t scanGuard = 10;      // Rx window padding in milliseconds
 
   // check if there are any upcoming Rx windows
   // if the Rx1 window has already started, you're too late, because most downlinks happen in Rx1
-  if(mod->hal->millis() - this->rxDelayStart > (this->rxDelays[0] - scanGuard)) {
+  RadioLibTime_t now = mod->hal->millis();  // Fix the current timestamp to prevent negative delays
+  if(now > this->rxDelayStart + this->rxDelays[0] - scanGuard) {
     // if between start of Rx1 and end of Rx2, wait until Rx2 closes
-    if(mod->hal->millis() - this->rxDelayStart < this->rxDelays[1]) {
-      mod->hal->delay(this->rxDelays[1] + this->rxDelayStart - mod->hal->millis());
+    if(now < this->rxDelayStart + this->rxDelays[1]) {
+      mod->hal->delay(this->rxDelays[1] + this->rxDelayStart - now);
     }
     // update the end timestamp in case user got stuck between uplink and downlink
     this->rxDelayEnd = mod->hal->millis();
     return(RADIOLIB_ERR_NO_RX_WINDOW);
   }
 
-  // configure for downlink
-  int16_t state = this->configureChannel(RADIOLIB_LORAWAN_CHANNEL_DIR_DOWNLINK);
+  // set the physical layer configuration for downlink
+  int16_t state = this->setPhyProperties(RADIOLIB_LORAWAN_CHANNEL_DIR_DOWNLINK);
   RADIOLIB_ASSERT(state);
 
-  // downlink messages are sent with inverted IQ
-  if(!this->FSK) {
-    state = this->phyLayer->invertIQ(true);
-    RADIOLIB_ASSERT(state);
-  }
-
   // create the masks that are required for receiving downlinks
   uint16_t irqFlags = 0x0000;
   uint16_t irqMask = 0x0000;
@@ -1182,14 +1162,16 @@ int16_t LoRaWANNode::downlinkCommon() {
     downlinkAction = false;
 
     // calculate the Rx timeout
-    // according to the spec, this must be at least enough time to effectively detect a preamble
-    // but pad it a bit on both sides (start and end) to make sure it is wide enough
     RadioLibTime_t timeoutHost = this->phyLayer->getTimeOnAir(0) + 2*scanGuard*1000;
     RadioLibTime_t timeoutMod  = this->phyLayer->calculateRxTimeout(timeoutHost);
 
     // wait for the start of the Rx window
+    RadioLibTime_t waitLen = this->rxDelayStart + this->rxDelays[i] - mod->hal->millis();
+    // make sure that no underflow occured; if so, clip the delay (although this will likely miss any downlink)
+    if(waitLen > this->rxDelays[i]) {
+      waitLen = this->rxDelays[i];
+    }
     // the waiting duration is shortened a bit to cover any possible timing errors
-    RadioLibTime_t waitLen = this->rxDelays[i] - (mod->hal->millis() - this->rxDelayStart);
     if(waitLen > scanGuard) {
       waitLen -= scanGuard;
     }
@@ -1215,7 +1197,8 @@ int16_t LoRaWANNode::downlinkCommon() {
       RADIOLIB_ASSERT(state);
 
       DataRate_t dataRate;
-      findDataRate(this->rx2.drMax, &dataRate);
+      state = findDataRate(this->rx2.drMax, &dataRate);
+      RADIOLIB_ASSERT(state);
       state = this->phyLayer->setDataRate(dataRate);
       RADIOLIB_ASSERT(state);
     }
@@ -1687,16 +1670,51 @@ bool LoRaWANNode::verifyMIC(uint8_t* msg, size_t len, uint8_t* key) {
   return(true);
 }
 
-int16_t LoRaWANNode::setPhyProperties() {
+int16_t LoRaWANNode::setPhyProperties(uint8_t dir) {
   // set the physical layer configuration
-  int8_t pwr = this->txPowerMax - this->txPowerCur * 2;
-  int16_t state = RADIOLIB_ERR_INVALID_OUTPUT_POWER;
-  while(state == RADIOLIB_ERR_INVALID_OUTPUT_POWER) {
-    // go from the highest power and lower it until we hit one supported by the module
-    state = this->phyLayer->setOutputPower(pwr--);
+  RADIOLIB_DEBUG_PROTOCOL_PRINTLN("");
+  RADIOLIB_DEBUG_PROTOCOL_PRINTLN("PHY: Frequency %cL = %6.3f MHz", dir ? 'D' : 'U', this->currentChannels[dir].freq);
+  int16_t state = this->phyLayer->setFrequency(this->currentChannels[dir].freq);
+  RADIOLIB_ASSERT(state);
+
+  // if this channel is an FSK channel, toggle the FSK switch
+  if(this->band->dataRates[this->dataRates[dir]] == RADIOLIB_LORAWAN_DATA_RATE_FSK_50_K) {
+    this->FSK = true;
+  } else {
+    this->FSK = false;
   }
+
+  int8_t pwr = this->txPowerMax - this->txPowerCur * 2;
+  
+  // at this point, assume that Tx power value is already checked, so ignore the return value
+  (void)this->phyLayer->checkOutputPower(pwr, &pwr);
+  state = this->phyLayer->setOutputPower(pwr);
   RADIOLIB_ASSERT(state);
 
+  DataRate_t dr;
+  state = findDataRate(this->dataRates[dir], &dr);
+  RADIOLIB_ASSERT(state);
+  state = this->phyLayer->setDataRate(dr);
+  RADIOLIB_ASSERT(state);
+
+  RADIOLIB_DEBUG_PROTOCOL_PRINTLN("PHY: SF = %d, TX = %d dBm, BW = %6.3f kHz, CR = 4/%d", 
+                            dr.lora.spreadingFactor, pwr, dr.lora.bandwidth, dr.lora.codingRate);
+
+  if(this->FSK) {
+    state = this->phyLayer->setDataShaping(RADIOLIB_SHAPING_1_0);
+    RADIOLIB_ASSERT(state);
+    state = this->phyLayer->setEncoding(RADIOLIB_ENCODING_WHITENING);
+  }
+
+  // downlink messages are sent with inverted IQ
+  if(dir == RADIOLIB_LORAWAN_CHANNEL_DIR_DOWNLINK) {
+    if(!this->FSK) {
+      state = this->phyLayer->invertIQ(true);
+      RADIOLIB_ASSERT(state);
+    }
+  }
+
+  // this only needs to be done once-ish
   uint8_t syncWord[3] = { 0 };
   uint8_t syncWordLen = 0;
   size_t preLen = 0;
@@ -1987,7 +2005,8 @@ void LoRaWANNode::setDwellTime(bool enable, RadioLibTime_t msPerUplink) {
 uint8_t LoRaWANNode::maxPayloadDwellTime() {
   // configure current datarate
   DataRate_t dr;
-  findDataRate(this->dataRates[RADIOLIB_LORAWAN_CHANNEL_DIR_UPLINK], &dr);
+  // TODO this may fail horribly?
+  (void)findDataRate(this->dataRates[RADIOLIB_LORAWAN_CHANNEL_DIR_UPLINK], &dr);
   (void)this->phyLayer->setDataRate(dr);
   uint8_t minPayLen = 0;
   uint8_t maxPayLen = 255;
@@ -2035,6 +2054,8 @@ int16_t LoRaWANNode::setTxPower(int8_t txPower) {
 }
 
 int16_t LoRaWANNode::findDataRate(uint8_t dr, DataRate_t* dataRate) {
+  int16_t state = RADIOLIB_ERR_UNKNOWN;
+
   uint8_t dataRateBand = this->band->dataRates[dr];
 
   if(dataRateBand & RADIOLIB_LORAWAN_DATA_RATE_FSK_50_K) {
@@ -2059,50 +2080,37 @@ int16_t LoRaWANNode::findDataRate(uint8_t dr, DataRate_t* dataRate) {
     
     dataRate->lora.spreadingFactor = ((dataRateBand & 0x70) >> 4) + 6;
     dataRate->lora.codingRate = (dataRateBand & 0x03) + 5;
-    RADIOLIB_DEBUG_PROTOCOL_PRINTLN("PHY: SF = %d, BW = %6.3f kHz, CR = 4/%d", 
-                            dataRate->lora.spreadingFactor, dataRate->lora.bandwidth, dataRate->lora.codingRate);
   }
 
-  return(RADIOLIB_ERR_NONE);
-}
-
-int16_t LoRaWANNode::configureChannel(uint8_t dir) {
-  // set the frequency
-  RADIOLIB_DEBUG_PROTOCOL_PRINTLN("");
-  RADIOLIB_DEBUG_PROTOCOL_PRINTLN("PHY: Frequency %cL = %6.3f MHz", dir ? 'D' : 'U', this->currentChannels[dir].freq);
-  int state = this->phyLayer->setFrequency(this->currentChannels[dir].freq);
-  RADIOLIB_ASSERT(state);
-
-  // if this channel is an FSK channel, toggle the FSK switch
-  if(this->band->dataRates[this->dataRates[dir]] == RADIOLIB_LORAWAN_DATA_RATE_FSK_50_K) {
-    this->FSK = true;
-  } else {
-    this->FSK = false;
-  }
-
-  DataRate_t dr;
-  findDataRate(this->dataRates[dir], &dr);
-  state = this->phyLayer->setDataRate(dr);
-  RADIOLIB_ASSERT(state);
-
-  if(this->FSK) {
-    state = this->phyLayer->setDataShaping(RADIOLIB_SHAPING_1_0);
-    RADIOLIB_ASSERT(state);
-    state = this->phyLayer->setEncoding(RADIOLIB_ENCODING_WHITENING);
-  }
+  state = this->phyLayer->checkDataRate(*dataRate);
 
   return(state);
 }
 
-bool LoRaWANNode::sendMacCommandReq(uint8_t cid) {
+int16_t LoRaWANNode::sendMacCommandReq(uint8_t cid) {
   bool valid = false;
   for(size_t i = 0; i < RADIOLIB_LORAWAN_NUM_MAC_COMMANDS; i++) {
     if(MacTable[i].cid == cid) {
       valid = MacTable[i].user;
     }
   }
-  if(!valid)
-    return(false);
+  if(!valid) {
+    RADIOLIB_DEBUG_PROTOCOL_PRINTLN("You are not allowed to request this MAC command");
+    return(RADIOLIB_ERR_INVALID_CID);
+  }
+
+  // if there are already 15 MAC bytes in the uplink queue, we can't add a new one
+  if(this->commandsUp.len + 1 > RADIOLIB_LORAWAN_FHDR_FOPTS_MAX_LEN) {
+    RADIOLIB_DEBUG_PROTOCOL_PRINTLN("The maximum number of FOpts payload was reached");
+    return(RADIOLIB_ERR_COMMAND_QUEUE_FULL);
+  }
+  if(this->commandsUp.numCommands > RADIOLIB_LORAWAN_MAC_COMMAND_QUEUE_SIZE) {
+    RADIOLIB_DEBUG_PROTOCOL_PRINTLN("The RadioLib internal MAC command queue was full");
+    return(RADIOLIB_ERR_COMMAND_QUEUE_FULL);
+  }
+
+  // delete any prior requests for this MAC command, in case this is requested more than once
+  (void)deleteMacCommand(cid, &this->commandsUp);
   
   LoRaWANMacCommand_t cmd = {
     .cid = cid,
@@ -2182,8 +2190,6 @@ bool LoRaWANNode::execMacCommand(LoRaWANMacCommand_t* cmd) {
     case(RADIOLIB_LORAWAN_MAC_LINK_ADR): {
       int16_t state = RADIOLIB_ERR_UNKNOWN;
       // get the ADR configuration
-      // per spec, all these configuration should only be set if all ACKs are set, otherwise retain previous state
-      // but we don't bother and try to set each individual command
       uint8_t drUp = (cmd->payload[0] & 0xF0) >> 4;
       uint8_t txSteps = cmd->payload[0] & 0x0F;
       bool isInternalTxDr = cmd->payload[3] >> 7;
@@ -2193,19 +2199,15 @@ bool LoRaWANNode::execMacCommand(LoRaWANMacCommand_t* cmd) {
       uint8_t nbTrans = cmd->payload[3] & 0x0F;
       RADIOLIB_DEBUG_PROTOCOL_PRINTLN("LinkADRReq: dataRate = %d, txSteps = %d, chMask = 0x%04x, chMaskCntl = %d, nbTrans = %d", drUp, txSteps, chMask, chMaskCntl, nbTrans);
 
-      // apply the configuration
+      // try to apply the datarate configuration
       uint8_t drAck = 0;
       if(drUp == 0x0F) {  // keep the same
         drAck = 1;
 
-        // replace the 'placeholder' with the current actual value for saving
-        cmd->payload[0] = (cmd->payload[0] & 0x0F) | (this->dataRates[RADIOLIB_LORAWAN_CHANNEL_DIR_UPLINK] << 4);
-
       } else if (this->band->dataRates[drUp] != RADIOLIB_LORAWAN_DATA_RATE_UNUSED) {
         // check if the module supports this data rate
         DataRate_t dr;
-        findDataRate(drUp, &dr);
-        state = this->phyLayer->checkDataRate(dr);
+        state = findDataRate(drUp, &dr);
         if(state == RADIOLIB_ERR_NONE) {
           uint8_t drDown = getDownlinkDataRate(drUp, this->rx1DrOffset, this->band->rx1DataRateBase,
                                                this->currentChannels[RADIOLIB_LORAWAN_CHANNEL_DIR_DOWNLINK].drMin,
@@ -2215,6 +2217,7 @@ bool LoRaWANNode::execMacCommand(LoRaWANMacCommand_t* cmd) {
           drAck = 1;
         } else {
           RADIOLIB_DEBUG_PROTOCOL_PRINTLN("ADR failed to configure dataRate %d, code %d!", drUp, state);
+          drUp = 0x0F;  // set value to 'keep the same'
         }
       
       }
@@ -2224,25 +2227,20 @@ bool LoRaWANNode::execMacCommand(LoRaWANMacCommand_t* cmd) {
       if(txSteps == 0x0F) {
         pwrAck = 1;
 
-        // replace the 'placeholder' with the current actual value for saving
-        cmd->payload[0] = (cmd->payload[0] & 0xF0) | this->txPowerCur;
-
       } else {
-        int8_t pwr = this->txPowerMax - 2*txSteps;
-        RADIOLIB_DEBUG_PROTOCOL_PRINTLN("PHY: TX = %d dBm", pwr);
-        state = RADIOLIB_ERR_INVALID_OUTPUT_POWER;
-        while(state == RADIOLIB_ERR_INVALID_OUTPUT_POWER) {
-          // go from the highest power and lower it until we hit one supported by the module
-          state = this->phyLayer->setOutputPower(pwr--);
-        }
-        // only acknowledge if the requested datarate was succesfully configured
-        if(state == RADIOLIB_ERR_NONE) {
+        int8_t power = this->txPowerMax - 2*txSteps;
+        int8_t powerActual = 0;
+        state = this->phyLayer->checkOutputPower(power, &powerActual);
+        // only acknowledge if the radio is able to operate at or below the requested power level
+        if(state == RADIOLIB_ERR_NONE || (state == RADIOLIB_ERR_INVALID_OUTPUT_POWER && powerActual < power)) {
           pwrAck = 1;
           this->txPowerCur = txSteps;
+        } else {
+          RADIOLIB_DEBUG_PROTOCOL_PRINTLN("ADR failed to configure Tx power %d, code %d!", power, state);
+          txSteps = 0x0F;  // set value to 'keep the same'
         }
       }
 
-
       uint8_t chMaskAck = 1;
       // only apply channel mask when the RFU bit is not set
       // (which is only set in internal MAC commands for changing Tx/Dr)
@@ -2269,12 +2267,23 @@ bool LoRaWANNode::execMacCommand(LoRaWANMacCommand_t* cmd) {
         }
       }
 
-      if(nbTrans == 0) {  // keep the same
-        cmd->payload[3] = (cmd->payload[3] & 0xF0) | this->nbTrans; // set current number of retransmissions for saving
-      } else {
+      if(nbTrans) {  // if there is a value for NbTrans, set this value
         this->nbTrans = nbTrans;
       }
 
+      // replace 'placeholder' or failed values with the current values for saving
+      // per spec, all these configuration should only be set if all ACKs are set, otherwise retain previous state
+      // but we don't bother and try to set each individual command
+      if(drUp == 0x0F || !drAck) {
+        cmd->payload[0] = (cmd->payload[0] & 0x0F) | (this->dataRates[RADIOLIB_LORAWAN_CHANNEL_DIR_UPLINK] << 4);
+      }
+      if(txSteps == 0x0F || !pwrAck) {
+        cmd->payload[0] = (cmd->payload[0] & 0xF0) | this->txPowerCur;
+      }
+      if(nbTrans == 0) {
+        cmd->payload[3] = (cmd->payload[3] & 0xF0) | this->nbTrans;
+      }
+
       if(this->band->bandType == RADIOLIB_LORAWAN_BAND_DYNAMIC) {
         // if RFU bit is set, this is just a change in Datarate or TxPower, so read ADR command and overwrite first byte
         if(isInternalTxDr) {
@@ -2801,6 +2810,10 @@ uint64_t LoRaWANNode::getDevAddr() {
   return(this->devAddr);
 }
 
+RadioLibTime_t LoRaWANNode::getLastToA() {
+  return(this->lastToA);
+}
+
 // The following function enables LMAC, a CSMA scheme for LoRa as specified 
 // in the LoRa Alliance Technical Recommendation #13.
 // A user may enable CSMA to provide frames an additional layer of protection from interference.
diff --git a/src/protocols/LoRaWAN/LoRaWAN.h b/src/protocols/LoRaWAN/LoRaWAN.h
index 061a20b2d..9359c2ae2 100644
--- a/src/protocols/LoRaWAN/LoRaWAN.h
+++ b/src/protocols/LoRaWAN/LoRaWAN.h
@@ -159,6 +159,12 @@
 #define RADIOLIB_LORAWAN_MIC_DATA_RATE_POS                      (3)
 #define RADIOLIB_LORAWAN_MIC_CH_INDEX_POS                       (4)
 
+// maximum allowed dwell time on bands that implement dwell time limitations
+#define RADIOLIB_LORAWAN_DWELL_TIME                             (400)
+
+// unused frame counter value
+#define RADIOLIB_LORAWAN_FCNT_NONE                              (0xFFFFFFFF)
+
 // MAC commands
 #define RADIOLIB_LORAWAN_NUM_MAC_COMMANDS                       (16)
 
@@ -179,15 +185,6 @@
 #define RADIOLIB_LORAWAN_MAC_REJOIN_PARAM_SETUP                 (0x0F)
 #define RADIOLIB_LORAWAN_MAC_PROPRIETARY                        (0x80)
 
-// maximum allowed dwell time on bands that implement dwell time limitations
-#define RADIOLIB_LORAWAN_DWELL_TIME                             (400)
-
-// unused LoRaWAN version
-#define RADIOLIB_LORAWAN_VERSION_NONE                           (0xFF)
-
-// unused frame counter value
-#define RADIOLIB_LORAWAN_FCNT_NONE                              (0xFFFFFFFF)
-
 // the length of internal MAC command queue - hopefully this is enough for most use cases
 #define RADIOLIB_LORAWAN_MAC_COMMAND_QUEUE_SIZE                 (9)
 
@@ -217,74 +214,109 @@ struct LoRaWANMacSpec_t {
   const bool user;
 };
 
-const LoRaWANMacSpec_t MacTable[RADIOLIB_LORAWAN_NUM_MAC_COMMANDS + 1] = {
+constexpr LoRaWANMacSpec_t MacTable[RADIOLIB_LORAWAN_NUM_MAC_COMMANDS + 1] = {
   { 0x00, 0, 0, false }, // not an actual MAC command, exists for index offsetting
-  { RADIOLIB_LORAWAN_MAC_RESET, 1, 1, false },
-  { RADIOLIB_LORAWAN_MAC_LINK_CHECK, 2, 0, true  },
-  { RADIOLIB_LORAWAN_MAC_LINK_ADR, 4, 1, false },
-  { RADIOLIB_LORAWAN_MAC_DUTY_CYCLE, 1, 0, false },
-  { RADIOLIB_LORAWAN_MAC_RX_PARAM_SETUP, 4, 1, false },
-  { RADIOLIB_LORAWAN_MAC_DEV_STATUS, 0, 2, false },
-  { RADIOLIB_LORAWAN_MAC_NEW_CHANNEL, 5, 1, false },
-  { RADIOLIB_LORAWAN_MAC_RX_TIMING_SETUP, 1, 0, false },
-  { RADIOLIB_LORAWAN_MAC_TX_PARAM_SETUP, 1, 0, false },
-  { RADIOLIB_LORAWAN_MAC_DL_CHANNEL, 4, 1, false },
-  { RADIOLIB_LORAWAN_MAC_REKEY, 1, 1, false },
-  { RADIOLIB_LORAWAN_MAC_ADR_PARAM_SETUP, 1, 0, false },
-  { RADIOLIB_LORAWAN_MAC_DEVICE_TIME, 5, 0, true  },
-  { RADIOLIB_LORAWAN_MAC_FORCE_REJOIN, 2, 0, false },
-  { RADIOLIB_LORAWAN_MAC_REJOIN_PARAM_SETUP, 1, 1, false },
-  { RADIOLIB_LORAWAN_MAC_PROPRIETARY, 5, 0, true  } 
+  { RADIOLIB_LORAWAN_MAC_RESET,               1, 1, false },
+  { RADIOLIB_LORAWAN_MAC_LINK_CHECK,          2, 0, true  },
+  { RADIOLIB_LORAWAN_MAC_LINK_ADR,            4, 1, false },
+  { RADIOLIB_LORAWAN_MAC_DUTY_CYCLE,          1, 0, false },
+  { RADIOLIB_LORAWAN_MAC_RX_PARAM_SETUP,      4, 1, false },
+  { RADIOLIB_LORAWAN_MAC_DEV_STATUS,          0, 2, false },
+  { RADIOLIB_LORAWAN_MAC_NEW_CHANNEL,         5, 1, false },
+  { RADIOLIB_LORAWAN_MAC_RX_TIMING_SETUP,     1, 0, false },
+  { RADIOLIB_LORAWAN_MAC_TX_PARAM_SETUP,      1, 0, false },
+  { RADIOLIB_LORAWAN_MAC_DL_CHANNEL,          4, 1, false },
+  { RADIOLIB_LORAWAN_MAC_REKEY,               1, 1, false },
+  { RADIOLIB_LORAWAN_MAC_ADR_PARAM_SETUP,     1, 0, false },
+  { RADIOLIB_LORAWAN_MAC_DEVICE_TIME,         5, 0, true  },
+  { RADIOLIB_LORAWAN_MAC_FORCE_REJOIN,        2, 0, false },
+  { RADIOLIB_LORAWAN_MAC_REJOIN_PARAM_SETUP,  1, 1, false },
+  { RADIOLIB_LORAWAN_MAC_PROPRIETARY,         5, 0, true  } 
+};
+
+/*!
+  \struct LoRaWANMacCommand_t
+  \brief Structure to save information about MAC command
+*/
+struct LoRaWANMacCommand_t {
+  /*! \brief The command ID */
+  uint8_t cid;
+
+  /*! \brief Payload buffer (5 bytes is the longest possible) */
+  uint8_t payload[5];
+
+  /*! \brief Length of the payload */
+  uint8_t len;
+
+  /*! \brief Repetition counter (the command will be uplinked repeat + 1 times) */
+  uint8_t repeat;
+};
+
+/*!
+  \struct LoRaWANMacCommandQueue_t
+  \brief Structure to hold information about a queue of MAC commands
+*/
+struct LoRaWANMacCommandQueue_t {
+  /*! \brief Number of commands in the queue */
+  uint8_t numCommands;
+
+  /*! \brief Total length of the queue */
+  uint8_t len;
+
+  /*! \brief MAC command buffer */
+  LoRaWANMacCommand_t commands[RADIOLIB_LORAWAN_MAC_COMMAND_QUEUE_SIZE];
 };
 
 #define RADIOLIB_LORAWAN_NONCES_VERSION_VAL (0x0001)
 
 enum LoRaWANSchemeBase_t {
-  RADIOLIB_LORAWAN_NONCES_VERSION     = 0x00, // 2 bytes
-  RADIOLIB_LORAWAN_NONCES_MODE        = 0x02, // 2 bytes
-  RADIOLIB_LORAWAN_NONCES_CLASS       = 0x04, // 1 byte
-  RADIOLIB_LORAWAN_NONCES_PLAN        = 0x05, // 1 byte
-  RADIOLIB_LORAWAN_NONCES_CHECKSUM    = 0x06, // 2 bytes
-  RADIOLIB_LORAWAN_NONCES_DEV_NONCE   = 0x08, // 2 bytes
-  RADIOLIB_LORAWAN_NONCES_JOIN_NONCE  = 0x0A, // 3 bytes
-  RADIOLIB_LORAWAN_NONCES_ACTIVE      = 0x0D, // 1 byte
-  RADIOLIB_LORAWAN_NONCES_SIGNATURE   = 0x0E, // 2 bytes
-  RADIOLIB_LORAWAN_NONCES_BUF_SIZE    = 0x10  // = 16 bytes
+  RADIOLIB_LORAWAN_NONCES_START       = 0x00,
+  RADIOLIB_LORAWAN_NONCES_VERSION     = RADIOLIB_LORAWAN_NONCES_START,                        // 2 bytes
+  RADIOLIB_LORAWAN_NONCES_MODE        = RADIOLIB_LORAWAN_NONCES_VERSION + sizeof(uint16_t),   // 2 bytes
+  RADIOLIB_LORAWAN_NONCES_CLASS       = RADIOLIB_LORAWAN_NONCES_MODE + sizeof(uint16_t),      // 1 byte
+  RADIOLIB_LORAWAN_NONCES_PLAN        = RADIOLIB_LORAWAN_NONCES_CLASS + sizeof(uint8_t),      // 1 byte
+  RADIOLIB_LORAWAN_NONCES_CHECKSUM    = RADIOLIB_LORAWAN_NONCES_PLAN + sizeof(uint8_t),       // 2 bytes
+  RADIOLIB_LORAWAN_NONCES_DEV_NONCE   = RADIOLIB_LORAWAN_NONCES_CHECKSUM + sizeof(uint16_t),  // 2 bytes
+  RADIOLIB_LORAWAN_NONCES_JOIN_NONCE  = RADIOLIB_LORAWAN_NONCES_DEV_NONCE + sizeof(uint16_t), // 3 bytes
+  RADIOLIB_LORAWAN_NONCES_ACTIVE      = RADIOLIB_LORAWAN_NONCES_JOIN_NONCE + 3,               // 1 byte
+  RADIOLIB_LORAWAN_NONCES_SIGNATURE   = RADIOLIB_LORAWAN_NONCES_ACTIVE + sizeof(uint8_t),     // 2 bytes
+  RADIOLIB_LORAWAN_NONCES_BUF_SIZE    = RADIOLIB_LORAWAN_NONCES_SIGNATURE + sizeof(uint16_t)  // Nonces buffer size
 };
 
 enum LoRaWANSchemeSession_t {
-  RADIOLIB_LORAWAN_SESSION_NWK_SENC_KEY       = 0x00,   // 16 bytes
-  RADIOLIB_LORAWAN_SESSION_APP_SKEY           = 0x10,   // 16 bytes
-  RADIOLIB_LORAWAN_SESSION_FNWK_SINT_KEY      = 0x20,   // 16 bytes
-  RADIOLIB_LORAWAN_SESSION_SNWK_SINT_KEY      = 0x30,   // 16 bytes
-  RADIOLIB_LORAWAN_SESSION_DEV_ADDR           = 0x40,   // 4 bytes
-  RADIOLIB_LORAWAN_SESSION_NONCES_SIGNATURE   = 0x44,   // 2 bytes
-  RADIOLIB_LORAWAN_SESSION_A_FCNT_DOWN        = 0x46, 	// 4 bytes
-  RADIOLIB_LORAWAN_SESSION_CONF_FCNT_UP       = 0x4A, 	// 4 bytes
-  RADIOLIB_LORAWAN_SESSION_CONF_FCNT_DOWN     = 0x4E, 	// 4 bytes
-  RADIOLIB_LORAWAN_SESSION_RJ_COUNT0          = 0x52, 	// 2 bytes
-  RADIOLIB_LORAWAN_SESSION_RJ_COUNT1          = 0x54, 	// 2 bytes
-  RADIOLIB_LORAWAN_SESSION_HOMENET_ID         = 0x56, 	// 4 bytes
-  RADIOLIB_LORAWAN_SESSION_VERSION            = 0x5A, 	// 1 byte
-  RADIOLIB_LORAWAN_SESSION_DUTY_CYCLE         = 0x5B, 	// 1 byte
-  RADIOLIB_LORAWAN_SESSION_RX_PARAM_SETUP     = 0x5C, 	// 4 bytes
-  RADIOLIB_LORAWAN_SESSION_RX_TIMING_SETUP    = 0x60, 	// 1 byte
-  RADIOLIB_LORAWAN_SESSION_TX_PARAM_SETUP     = 0x61, 	// 1 byte
-  RADIOLIB_LORAWAN_SESSION_ADR_PARAM_SETUP    = 0x62, 	// 1 byte
-  RADIOLIB_LORAWAN_SESSION_REJOIN_PARAM_SETUP = 0x63, 	// 1 byte
-  RADIOLIB_LORAWAN_SESSION_BEACON_FREQ        = 0x64, 	// 3 bytes
-  RADIOLIB_LORAWAN_SESSION_PING_SLOT_CHANNEL  = 0x67, 	// 4 bytes
-  RADIOLIB_LORAWAN_SESSION_PERIODICITY        = 0x6B, 	// 1 byte
-  RADIOLIB_LORAWAN_SESSION_LAST_TIME          = 0x6C, 	// 4 bytes
-  RADIOLIB_LORAWAN_SESSION_UL_CHANNELS        = 0x70, 	// 16*8 bytes
-  RADIOLIB_LORAWAN_SESSION_DL_CHANNELS        = 0xF0,   // 16*4 bytes
-  RADIOLIB_LORAWAN_SESSION_MAC_QUEUE_UL       = 0x0130, // 9*8+2 bytes
-  RADIOLIB_LORAWAN_SESSION_N_FCNT_DOWN        = 0x017A, // 4 bytes
-  RADIOLIB_LORAWAN_SESSION_ADR_FCNT           = 0x017E, // 4 bytes
-  RADIOLIB_LORAWAN_SESSION_LINK_ADR           = 0x0182, // 4 bytes
-  RADIOLIB_LORAWAN_SESSION_FCNT_UP            = 0x0186, // 4 bytes
-  RADIOLIB_LORAWAN_SESSION_SIGNATURE          = 0x018A, // 2 bytes
-  RADIOLIB_LORAWAN_SESSION_BUF_SIZE           = 0x018C  // 396 bytes
+  RADIOLIB_LORAWAN_SESSION_START              = 0x00,
+  RADIOLIB_LORAWAN_SESSION_NWK_SENC_KEY       = RADIOLIB_LORAWAN_SESSION_START,                 // 16 bytes
+  RADIOLIB_LORAWAN_SESSION_APP_SKEY           = RADIOLIB_LORAWAN_SESSION_NWK_SENC_KEY + RADIOLIB_AES128_BLOCK_SIZE,   // 16 bytes
+  RADIOLIB_LORAWAN_SESSION_FNWK_SINT_KEY      = RADIOLIB_LORAWAN_SESSION_APP_SKEY + RADIOLIB_AES128_BLOCK_SIZE,       // 16 bytes
+  RADIOLIB_LORAWAN_SESSION_SNWK_SINT_KEY      = RADIOLIB_LORAWAN_SESSION_FNWK_SINT_KEY + RADIOLIB_AES128_BLOCK_SIZE,  // 16 bytes
+  RADIOLIB_LORAWAN_SESSION_DEV_ADDR           = RADIOLIB_LORAWAN_SESSION_SNWK_SINT_KEY + RADIOLIB_AES128_BLOCK_SIZE,  // 4 bytes
+  RADIOLIB_LORAWAN_SESSION_NONCES_SIGNATURE   = RADIOLIB_LORAWAN_SESSION_DEV_ADDR + sizeof(uint32_t),         // 2 bytes
+  RADIOLIB_LORAWAN_SESSION_A_FCNT_DOWN        = RADIOLIB_LORAWAN_SESSION_NONCES_SIGNATURE + sizeof(uint16_t), // 4 bytes
+  RADIOLIB_LORAWAN_SESSION_CONF_FCNT_UP       = RADIOLIB_LORAWAN_SESSION_A_FCNT_DOWN + sizeof(uint32_t), 	    // 4 bytes
+  RADIOLIB_LORAWAN_SESSION_CONF_FCNT_DOWN     = RADIOLIB_LORAWAN_SESSION_CONF_FCNT_UP + sizeof(uint32_t), 	  // 4 bytes
+  RADIOLIB_LORAWAN_SESSION_RJ_COUNT0          = RADIOLIB_LORAWAN_SESSION_CONF_FCNT_DOWN + sizeof(uint32_t), 	// 2 bytes
+  RADIOLIB_LORAWAN_SESSION_RJ_COUNT1          = RADIOLIB_LORAWAN_SESSION_RJ_COUNT0 + sizeof(uint16_t), 	      // 2 bytes
+  RADIOLIB_LORAWAN_SESSION_HOMENET_ID         = RADIOLIB_LORAWAN_SESSION_RJ_COUNT1 + sizeof(uint16_t), 	      // 4 bytes
+  RADIOLIB_LORAWAN_SESSION_VERSION            = RADIOLIB_LORAWAN_SESSION_HOMENET_ID + sizeof(uint32_t), 	    // 1 byte
+  RADIOLIB_LORAWAN_SESSION_DUTY_CYCLE         = RADIOLIB_LORAWAN_SESSION_VERSION + sizeof(uint8_t), 	        // 1 byte
+  RADIOLIB_LORAWAN_SESSION_RX_PARAM_SETUP     = RADIOLIB_LORAWAN_SESSION_DUTY_CYCLE + MacTable[RADIOLIB_LORAWAN_MAC_DUTY_CYCLE].lenDn, 	// 4 bytes
+  RADIOLIB_LORAWAN_SESSION_RX_TIMING_SETUP    = RADIOLIB_LORAWAN_SESSION_RX_PARAM_SETUP + MacTable[RADIOLIB_LORAWAN_MAC_RX_PARAM_SETUP].lenDn, 	// 1 byte
+  RADIOLIB_LORAWAN_SESSION_TX_PARAM_SETUP     = RADIOLIB_LORAWAN_SESSION_RX_TIMING_SETUP + MacTable[RADIOLIB_LORAWAN_MAC_RX_TIMING_SETUP].lenDn, 	// 1 byte
+  RADIOLIB_LORAWAN_SESSION_ADR_PARAM_SETUP    = RADIOLIB_LORAWAN_SESSION_TX_PARAM_SETUP + MacTable[RADIOLIB_LORAWAN_MAC_TX_PARAM_SETUP].lenDn, 	// 1 byte
+  RADIOLIB_LORAWAN_SESSION_REJOIN_PARAM_SETUP = RADIOLIB_LORAWAN_SESSION_ADR_PARAM_SETUP + MacTable[RADIOLIB_LORAWAN_MAC_ADR_PARAM_SETUP].lenDn, 	// 1 byte
+  RADIOLIB_LORAWAN_SESSION_BEACON_FREQ        = RADIOLIB_LORAWAN_SESSION_REJOIN_PARAM_SETUP + MacTable[RADIOLIB_LORAWAN_MAC_REJOIN_PARAM_SETUP].lenDn, 	// 3 bytes
+  RADIOLIB_LORAWAN_SESSION_PING_SLOT_CHANNEL  = RADIOLIB_LORAWAN_SESSION_BEACON_FREQ + 3, 	    // 4 bytes
+  RADIOLIB_LORAWAN_SESSION_PERIODICITY        = RADIOLIB_LORAWAN_SESSION_PING_SLOT_CHANNEL + 4, // 1 byte
+  RADIOLIB_LORAWAN_SESSION_LAST_TIME          = RADIOLIB_LORAWAN_SESSION_PERIODICITY + 1, 	    // 4 bytes
+  RADIOLIB_LORAWAN_SESSION_UL_CHANNELS        = RADIOLIB_LORAWAN_SESSION_LAST_TIME + 4, 	      // 16*5 bytes
+  RADIOLIB_LORAWAN_SESSION_DL_CHANNELS        = RADIOLIB_LORAWAN_SESSION_UL_CHANNELS + 16*MacTable[RADIOLIB_LORAWAN_MAC_NEW_CHANNEL].lenDn, // 16*4 bytes
+  RADIOLIB_LORAWAN_SESSION_MAC_QUEUE_UL       = RADIOLIB_LORAWAN_SESSION_DL_CHANNELS + 16*MacTable[RADIOLIB_LORAWAN_MAC_DL_CHANNEL].lenDn,  // 9*8+2 bytes
+  RADIOLIB_LORAWAN_SESSION_N_FCNT_DOWN        = RADIOLIB_LORAWAN_SESSION_MAC_QUEUE_UL + sizeof(LoRaWANMacCommandQueue_t), // 4 bytes
+  RADIOLIB_LORAWAN_SESSION_ADR_FCNT           = RADIOLIB_LORAWAN_SESSION_N_FCNT_DOWN + sizeof(uint32_t),      // 4 bytes
+  RADIOLIB_LORAWAN_SESSION_LINK_ADR           = RADIOLIB_LORAWAN_SESSION_ADR_FCNT + sizeof(uint32_t),         // 4 bytes
+  RADIOLIB_LORAWAN_SESSION_FCNT_UP            = RADIOLIB_LORAWAN_SESSION_LINK_ADR + MacTable[RADIOLIB_LORAWAN_MAC_LINK_ADR].lenDn,  // 4 bytes
+  RADIOLIB_LORAWAN_SESSION_SIGNATURE          = RADIOLIB_LORAWAN_SESSION_FCNT_UP + sizeof(uint32_t),          // 2 bytes
+  RADIOLIB_LORAWAN_SESSION_BUF_SIZE           = RADIOLIB_LORAWAN_SESSION_SIGNATURE + sizeof(uint16_t)         // Session buffer size
 };
 
 /*!
@@ -428,38 +460,6 @@ enum LoRaWANBandNum_t {
 // array of currently supported bands
 extern const LoRaWANBand_t* LoRaWANBands[];
 
-/*!
-  \struct LoRaWANMacCommand_t
-  \brief Structure to save information about MAC command
-*/
-struct LoRaWANMacCommand_t {
-  /*! \brief The command ID */
-  uint8_t cid;
-
-  /*! \brief Payload buffer (5 bytes is the longest possible) */
-  uint8_t payload[5];
-
-  /*! \brief Length of the payload */
-  uint8_t len;
-
-  /*! \brief Repetition counter (the command will be uplinked repeat + 1 times) */
-  uint8_t repeat;
-};
-/*!
-  \struct LoRaWANMacCommandQueue_t
-  \brief Structure to hold information about a queue of MAC commands
-*/
-struct LoRaWANMacCommandQueue_t {
-  /*! \brief Number of commands in the queue */
-  uint8_t numCommands;
-
-  /*! \brief Total length of the queue */
-  uint8_t len;
-
-  /*! \brief MAC command buffer */
-  LoRaWANMacCommand_t commands[RADIOLIB_LORAWAN_MAC_COMMAND_QUEUE_SIZE];
-};
-
 /*!
   \struct LoRaWANEvent_t
   \brief Structure to save extra information about uplink/downlink event.
@@ -567,15 +567,16 @@ class LoRaWANNode {
       \brief Join network by performing activation by personalization.
       In this procedure, all necessary configuration must be provided by the user.
       \param addr Device address.
-      \param nwkSKey Pointer to the network session AES-128 key (LoRaWAN 1.0) or MAC command network session key (LoRaWAN 1.1).
+      \param fNwkSIntKey Pointer to the Forwarding network session (LoRaWAN 1.1), NULL for LoRaWAN 1.0.
+      \param sNwkSIntKey Pointer to the Serving network session (LoRaWAN 1.1), NULL for LoRaWAN 1.0.
+      \param nwkSEncKey Pointer to the MAC command network session key [NwkSEncKey] (LoRaWAN 1.1) 
+                                    or network session AES-128 key [NwkSKey] (LoRaWAN 1.0).
       \param appSKey Pointer to the application session AES-128 key.
-      \param fNwkSIntKey Pointer to the Forwarding network session (LoRaWAN 1.1), unused for LoRaWAN 1.0.
-      \param sNwkSIntKey Pointer to the Serving network session (LoRaWAN 1.1), unused for LoRaWAN 1.0.
       \param force Set to true to force a new session, even if one exists.
       \param initialDr The datarate at which to send the first uplink and any subsequent uplinks (unless ADR is enabled)
       \returns \ref status_codes
     */
-    int16_t beginABP(uint32_t addr, uint8_t* nwkSKey, uint8_t* appSKey, uint8_t* fNwkSIntKey = NULL, uint8_t* sNwkSIntKey = NULL, bool force = false, uint8_t initialDr = RADIOLIB_LORAWAN_DATA_RATE_UNUSED);
+    int16_t beginABP(uint32_t addr, uint8_t* fNwkSIntKey, uint8_t* sNwkSIntKey, uint8_t* nwkSEncKey, uint8_t* appSKey, bool force = false, uint8_t initialDr = RADIOLIB_LORAWAN_DATA_RATE_UNUSED);
 
     /*! \brief Whether there is an ongoing session active */
     bool isJoined();
@@ -591,9 +592,9 @@ class LoRaWANNode {
       Only LinkCheck and DeviceTime are available to the user. 
       Other commands are ignored; duplicate MAC commands are discarded.
       \param cid ID of the MAC command
-      \returns Whether or not the MAC command was added to the queue.
+      \returns \ref status_codes
     */
-    bool sendMacCommandReq(uint8_t cid);
+    int16_t sendMacCommandReq(uint8_t cid);
 
     #if defined(RADIOLIB_BUILD_ARDUINO)
     /*!
@@ -835,6 +836,12 @@ class LoRaWANNode {
     */
     uint64_t getDevAddr();
 
+    /*!
+      \brief Get the Time-on-air of the last uplink message
+      \returns (RadioLibTime_t) time-on-air (ToA) of last uplink message
+    */
+   RadioLibTime_t getLastToA();
+
 #if !RADIOLIB_GODMODE
   private:
 #endif
@@ -964,7 +971,7 @@ class LoRaWANNode {
 
     // configure the common physical layer properties (preamble, sync word etc.)
     // channels must be configured separately by setupChannelsDyn()!
-    int16_t setPhyProperties();
+    int16_t setPhyProperties(uint8_t dir);
 
     // setup uplink/downlink channel data rates and frequencies
     // for dynamic channels, there is a small set of predefined channels
@@ -984,9 +991,6 @@ class LoRaWANNode {
     // find the first usable data rate for the given band
     int16_t findDataRate(uint8_t dr, DataRate_t* dataRate);
 
-    // configure channel based on cached data rate ID and frequency
-    int16_t configureChannel(uint8_t dir);
-
     // restore all available channels from persistent storage
     int16_t restoreChannels();
 
diff --git a/src/protocols/PhysicalLayer/PhysicalLayer.cpp b/src/protocols/PhysicalLayer/PhysicalLayer.cpp
index 822cc18a6..55e69329d 100644
--- a/src/protocols/PhysicalLayer/PhysicalLayer.cpp
+++ b/src/protocols/PhysicalLayer/PhysicalLayer.cpp
@@ -256,6 +256,12 @@ int16_t PhysicalLayer::setOutputPower(int8_t power) {
   return(RADIOLIB_ERR_UNSUPPORTED);
 }
 
+int16_t PhysicalLayer::checkOutputPower(int8_t power, int8_t* clipped) {
+  (void)power;
+  (void)clipped;
+  return(RADIOLIB_ERR_UNSUPPORTED);
+}
+
 int16_t PhysicalLayer::setSyncWord(uint8_t* sync, size_t len) {
   (void)sync;
   (void)len;
diff --git a/src/protocols/PhysicalLayer/PhysicalLayer.h b/src/protocols/PhysicalLayer/PhysicalLayer.h
index f27e79ea1..3d48eda2b 100644
--- a/src/protocols/PhysicalLayer/PhysicalLayer.h
+++ b/src/protocols/PhysicalLayer/PhysicalLayer.h
@@ -276,6 +276,14 @@ class PhysicalLayer {
     */
     virtual int16_t setOutputPower(int8_t power);
 
+    /*!
+      \brief Check if output power is configurable. Must be implemented in module class if the module supports it.
+      \param power Output power in dBm. The allowed range depends on the module used.
+      \param clipped Clipped output power value to what is possible within the module's range.
+      \returns \ref status_codes
+    */
+    virtual int16_t checkOutputPower(int8_t power, int8_t* clipped);
+
     /*!
       \brief Set sync word. Must be implemented in module class if the module supports it.
       \param sync Pointer to the sync word.