From 9fe3559e142a115d1d58501d0a78b02fc82602fd Mon Sep 17 00:00:00 2001
From: Henry Potgieter <hpotgieter@viscousbits.ca>
Date: Mon, 30 Mar 2026 00:36:09 -0400
Subject: [PATCH] Throw in changes based on meshtastic's support of the v4.3
 board

---
 Boards.h           |  6 +++---
 RNode_Firmware.ino |  6 +++++-
 sx126x.cpp         | 54 ++++++++++++++++++++++------------------------
 3 files changed, 34 insertions(+), 32 deletions(-)

diff --git a/Boards.h b/Boards.h
index 1e9cf42..9d69bf6 100644
--- a/Boards.h
+++ b/Boards.h
@@ -422,14 +422,14 @@
 
       #define LORA_LNA_GAIN  17
       #define LORA_LNA_GVT   12
-      #define LORA_PA_GC1109 true
+      #define LORA_PA_KCT8103L true
       #define LORA_PA_PWR_EN  7
       #define LORA_PA_CSD     2
-      #define LORA_PA_CPS    46
+      #define LORA_PA_CTX     5
 
       #define PA_MAX_OUTPUT  28
       #define PA_GAIN_POINTS 22
-      #define PA_GAIN_VALUES 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 10, 10, 9, 9, 8, 7
+      #define PA_GAIN_VALUES 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 12, 12, 11, 11, 10, 9, 8, 7
 
       const int pin_cs = 8;
       const int pin_busy = 13;
diff --git a/RNode_Firmware.ino b/RNode_Firmware.ino
index 5649206..1f13040 100644
--- a/RNode_Firmware.ino
+++ b/RNode_Firmware.ino
@@ -1767,7 +1767,11 @@ void sleep_now() {
         #endif
       #endif
       #if BOARD_MODEL == BOARD_HELTEC32_V4
-          digitalWrite(LORA_PA_CPS, LOW);
+          #if LORA_PA_KCT8103L
+            digitalWrite(LORA_PA_CTX, LOW);
+          #elif LORA_PA_GC1109
+            digitalWrite(LORA_PA_CPS, LOW);
+          #endif
           digitalWrite(LORA_PA_CSD, LOW);
           digitalWrite(LORA_PA_PWR_EN, LOW);
           digitalWrite(Vext, HIGH);
diff --git a/sx126x.cpp b/sx126x.cpp
index c67a4df..ddb7c07 100644
--- a/sx126x.cpp
+++ b/sx126x.cpp
@@ -343,7 +343,21 @@ int sx126x::begin(long frequency) {
   setPacketParams(_preambleLength, _implicitHeaderMode, _payloadLength, _crcMode);
 
   #if HAS_LORA_PA
-    #if LORA_PA_GC1109
+    #if LORA_PA_KCT8103L
+      // Enable Vfem_ctl for supply to PA power net.
+      pinMode(LORA_PA_PWR_EN, OUTPUT);
+      digitalWrite(LORA_PA_PWR_EN, HIGH);
+
+      // Enable KCT8103L: CSD=HIGH activates the chip.
+      pinMode(LORA_PA_CSD, OUTPUT);
+      digitalWrite(LORA_PA_CSD, HIGH);
+
+      // CTX=LOW selects LNA/RX mode by default.
+      // CTX=HIGH switches to PA/TX mode.
+      // Must be toggled on each TX/RX transition.
+      pinMode(LORA_PA_CTX, OUTPUT);
+      digitalWrite(LORA_PA_CTX, LOW);
+    #elif LORA_PA_GC1109
       // Enable Vfem_ctl for supply to
       // PA power net.
       pinMode(LORA_PA_PWR_EN, OUTPUT);
@@ -353,21 +367,9 @@ int sx126x::begin(long frequency) {
       pinMode(LORA_PA_CSD, OUTPUT);
       digitalWrite(LORA_PA_CSD, HIGH);
 
-      // Keep PA CPS low until actual
-      // transmit. Does it save power?
-      // Who knows? Will have to measure.
-      // Note from the future: Nope.
-      // Power consumption is the same,
-      // and turning it on and off is
-      // not something that it likes.
-      // Keeping it high for now.
+      // Keep PA CPS high permanently.
       pinMode(LORA_PA_CPS, OUTPUT);
       digitalWrite(LORA_PA_CPS, HIGH);
-
-      // On Heltec V4, the PA CTX pin
-      // is driven by the SX1262 DIO2
-      // pin directly, so we do not
-      // need to manually raise this.
     #endif
   #endif
 
@@ -378,12 +380,11 @@ void sx126x::end() { sleep(); SPI.end(); _preinit_done = false; }
 
 int sx126x::beginPacket(int implicitHeader) {
   #if HAS_LORA_PA
-    #if LORA_PA_GC1109
-      // Enable PA CPS for transmit
-      // digitalWrite(LORA_PA_CPS, HIGH);
-      // Disabled since we're keeping it
-      // on permanently as long as the
-      // radio is powered up.
+    #if LORA_PA_KCT8103L
+      // CTX=HIGH: switch KCT8103L to PA/TX mode.
+      digitalWrite(LORA_PA_CTX, HIGH);
+    #elif LORA_PA_GC1109
+      // CPS kept HIGH permanently, no action needed.
     #endif
   #endif
 
@@ -595,14 +596,11 @@ void sx126x::onReceive(void(*callback)(int)){
 
 void sx126x::receive(int size) {
   #if HAS_LORA_PA
-    #if LORA_PA_GC1109
-      // Disable PA CPS for receive
-      // digitalWrite(LORA_PA_CPS, LOW);
-      // That turned out to be a bad idea.
-      // The LNA goes wonky if it's toggled
-      // on and off too quickly. We'll keep
-      // it on permanently, as long as the
-      // radio is powered up.
+    #if LORA_PA_KCT8103L
+      // CTX=LOW: switch KCT8103L to LNA/RX mode.
+      digitalWrite(LORA_PA_CTX, LOW);
+    #elif LORA_PA_GC1109
+      // CPS kept HIGH permanently, no action needed.
     #endif
   #endif