From 8c80c10d2a0bc1dff1853252610154eae0192635 Mon Sep 17 00:00:00 2001
From: Scott Powell <sqij@protonmail.com>
Date: Mon, 30 Jun 2025 18:57:24 +1000
Subject: [PATCH 1/3] * CustomLR1110::getTimeOnAir(), copied from sx1262

---
 src/helpers/CustomLR1110.h | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/src/helpers/CustomLR1110.h b/src/helpers/CustomLR1110.h
index 3451aac1..d431dac1 100644
--- a/src/helpers/CustomLR1110.h
+++ b/src/helpers/CustomLR1110.h
@@ -9,6 +9,35 @@ class CustomLR1110 : public LR1110 {
   public:
     CustomLR1110(Module *mod) : LR1110(mod) { }
 
+    RadioLibTime_t getTimeOnAir(size_t len) override {
+      uint32_t symbolLength_us = ((uint32_t)(1000 * 10) << this->spreadingFactor) / (this->bandwidthKhz * 10) ;
+      uint8_t sfCoeff1_x4 = 17; // (4.25 * 4)
+      uint8_t sfCoeff2 = 8;
+      if(this->spreadingFactor == 5 || this->spreadingFactor == 6) {
+        sfCoeff1_x4 = 25; // 6.25 * 4
+        sfCoeff2 = 0;
+      }
+      uint8_t sfDivisor = 4*this->spreadingFactor;
+      if(symbolLength_us >= 16000) {
+        sfDivisor = 4*(this->spreadingFactor - 2);
+      }
+      const int8_t bitsPerCrc = 16;
+      const int8_t N_symbol_header = this->headerType == RADIOLIB_SX126X_LORA_HEADER_EXPLICIT ? 20 : 0;
+
+      // numerator of equation in section 6.1.4 of SX1268 datasheet v1.1 (might not actually be bitcount, but it has len * 8)
+      int16_t bitCount = (int16_t) 8 * len + this->crcTypeLoRa * bitsPerCrc - 4 * this->spreadingFactor  + sfCoeff2 + N_symbol_header;
+      if(bitCount < 0) {
+        bitCount = 0;
+      }
+      // add (sfDivisor) - 1 to the numerator to give integer CEIL(...)
+      uint16_t nPreCodedSymbols = (bitCount + (sfDivisor - 1)) / (sfDivisor);
+
+      // preamble can be 65k, therefore nSymbol_x4 needs to be 32 bit
+      uint32_t nSymbol_x4 = (this->preambleLengthLoRa + 8) * 4 + sfCoeff1_x4 + nPreCodedSymbols * (this->codingRate + 4) * 4;
+
+      return((symbolLength_us * nSymbol_x4) / 4);
+    }
+
     bool isReceiving() {
       uint16_t irq = getIrqStatus();
       bool detected = ((irq & LR1110_IRQ_HEADER_VALID) || (irq & LR1110_IRQ_HAS_PREAMBLE));

From dcb7ffa92ee470896380eb191730c4a45b983716 Mon Sep 17 00:00:00 2001
From: JQ <jquatier@gmail.com>
Date: Wed, 2 Jul 2025 08:32:36 -0700
Subject: [PATCH 2/3] fixing radio include order for heltec paper

---
 variants/heltec_wireless_paper/target.h | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/variants/heltec_wireless_paper/target.h b/variants/heltec_wireless_paper/target.h
index f06eead3..7d901c01 100644
--- a/variants/heltec_wireless_paper/target.h
+++ b/variants/heltec_wireless_paper/target.h
@@ -2,10 +2,10 @@
 
 #define RADIOLIB_STATIC_ONLY 1
 #include <RadioLib.h>
-#include <helpers/AutoDiscoverRTCClock.h>
-#include <helpers/CustomSX1262Wrapper.h>
-#include <helpers/HeltecV3Board.h>
 #include <helpers/RadioLibWrappers.h>
+#include <helpers/HeltecV3Board.h>
+#include <helpers/CustomSX1262Wrapper.h>
+#include <helpers/AutoDiscoverRTCClock.h>
 #include <helpers/SensorManager.h>
 #ifdef DISPLAY_CLASS
 #include <helpers/ui/E213Display.h>

From ca422bbafbebea98083d08fadf58902a77363fc3 Mon Sep 17 00:00:00 2001
From: JQ <jquatier@gmail.com>
Date: Wed, 2 Jul 2025 14:37:11 -0700
Subject: [PATCH 3/3] fix ble pin

---
 variants/heltec_wireless_paper/platformio.ini | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/variants/heltec_wireless_paper/platformio.ini b/variants/heltec_wireless_paper/platformio.ini
index 0b9ac38e..513ba4b9 100644
--- a/variants/heltec_wireless_paper/platformio.ini
+++ b/variants/heltec_wireless_paper/platformio.ini
@@ -40,7 +40,7 @@ build_flags =
   -D MAX_CONTACTS=100
   -D MAX_GROUP_CHANNELS=8
   -D DISPLAY_CLASS=E213Display
-  -D BLE_PIN_CODE=0  ; dynamic, random PIN
+  -D BLE_PIN_CODE=123456   ; dynamic, random PIN
   -D BLE_DEBUG_LOGGING=1
   -D OFFLINE_QUEUE_SIZE=256
 build_src_filter = ${Heltec_Wireless_Paper_base.build_src_filter}