From 9c9914a2c46a94ad5ac04353ceb6b018254f914e Mon Sep 17 00:00:00 2001
From: Sandeep Mistry <sandeep.mistry@gmail.com>
Date: Sun, 12 Mar 2017 16:17:13 -0400
Subject: [PATCH] Add option to specify PA output pin in Lora.setTxPower(...)
 (#2)

---
 API.md       |  7 ++++++-
 keywords.txt |  3 +++
 src/LoRa.cpp | 26 +++++++++++++++++++-------
 src/LoRa.h   |  5 ++++-
 4 files changed, 32 insertions(+), 9 deletions(-)

diff --git a/API.md b/API.md
index d1f5789..5cdef64 100644
--- a/API.md
+++ b/API.md
@@ -216,10 +216,15 @@ Change the TX power of the radio.
 
 ```arduino
 LoRa.setTxPower(txPower);
+
+LoRa.setTxPower(txPower, outputPin);
 ```
  * `txPower` - TX power in dB, defaults to `17`
+ * `outputPin` - (optional) PA output pin, supported values are `PA_OUTPUT_RFO_PIN` and `PA_OUTPUT_PA_BOOST_PIN`, defaults to `PA_OUTPUT_PA_BOOST_PIN`.
 
- Supported values are between `2` and `17`.
+Supported values are between `2` and `17` for `PA_OUTPUT_PA_BOOST_PIN`, `0` and `14` for `PA_OUTPUT_RFO_PIN`.
+
+Most modules have the PA output pin connected to PA BOOST,
 
 ### Frequency
 
diff --git a/keywords.txt b/keywords.txt
index 0ef2c76..cfa183f 100644
--- a/keywords.txt
+++ b/keywords.txt
@@ -52,3 +52,6 @@ dumpRegisters	KEYWORD2
 #######################################
 # Constants (LITERAL1)
 #######################################
+
+PA_OUTPUT_RFO_PIN	LITERAL1
+PA_OUTPUT_PA_BOOST_PIN	LITERAL1
diff --git a/src/LoRa.cpp b/src/LoRa.cpp
index 260917d..0d12c6b 100644
--- a/src/LoRa.cpp
+++ b/src/LoRa.cpp
@@ -297,15 +297,27 @@ void LoRaClass::sleep()
   writeRegister(REG_OP_MODE, MODE_LONG_RANGE_MODE | MODE_SLEEP);
 }
 
-void LoRaClass::setTxPower(int level)
+void LoRaClass::setTxPower(int level, int outputPin)
 {
-  if (level < 2) {
-    level = 2;
-  } else if (level > 17) {
-    level = 17;
-  }
+  if (PA_OUTPUT_RFO_PIN == outputPin) {
+    // RFO
+    if (level < 0) {
+      level = 0;
+    } else if (level > 14) {
+      level = 14;
+    }
 
-  writeRegister(REG_PA_CONFIG, PA_BOOST | (level - 2));
+    writeRegister(REG_PA_CONFIG, 0x70 | level);
+  } else {
+    // PA BOOST
+    if (level < 2) {
+      level = 2;
+    } else if (level > 17) {
+      level = 17;
+    }
+
+    writeRegister(REG_PA_CONFIG, PA_BOOST | (level - 2));
+  }
 }
 
 void LoRaClass::setFrequency(long frequency)
diff --git a/src/LoRa.h b/src/LoRa.h
index e8b551e..e69dd04 100644
--- a/src/LoRa.h
+++ b/src/LoRa.h
@@ -8,6 +8,9 @@
 #define LORA_DEFAULT_RESET_PIN 9
 #define LORA_DEFAULT_DIO0_PIN  2
 
+#define PA_OUTPUT_RFO_PIN      0
+#define PA_OUTPUT_PA_BOOST_PIN 1
+
 class LoRaClass : public Stream {
 public:
   LoRaClass();
@@ -38,7 +41,7 @@ public:
   void idle();
   void sleep();
 
-  void setTxPower(int level);
+  void setTxPower(int level, int outputPin = PA_OUTPUT_PA_BOOST_PIN);
   void setFrequency(long frequency);
   void setSpreadingFactor(int sf);
   void setSignalBandwidth(long sbw);