From 50e297b3d622013735344d1118b66bbe0cb19a12 Mon Sep 17 00:00:00 2001
From: "Pawel Spychalski (DzikuVx)" <pspychalski@gmail.com>
Date: Thu, 14 Dec 2017 23:41:14 +0100
Subject: [PATCH] Packet reading is now down in single SPI transaction

---
 .vscode/arduino.json |  2 +-
 crossbow.ino         | 16 ++++++++++------
 lora.cpp             | 46 +++++++++++++++++++++++++++++++++++++---------
 lora.h               |  9 +++++++--
 4 files changed, 55 insertions(+), 18 deletions(-)

diff --git a/.vscode/arduino.json b/.vscode/arduino.json
index e0b924b..488acc1 100644
--- a/.vscode/arduino.json
+++ b/.vscode/arduino.json
@@ -1,6 +1,6 @@
 {
     "board": "bsfrance:avr:lora32u4",
     "sketch": "crossbow.ino",
-    "port": "COM17",
+    "port": "COM4",
     "output": "./build"
 }
\ No newline at end of file
diff --git a/crossbow.ino b/crossbow.ino
index 39fc969..4870558 100644
--- a/crossbow.ino
+++ b/crossbow.ino
@@ -1,10 +1,10 @@
-#define DEVICE_MODE_TX
-// #define DEVICE_MODE_RX
+// #define DEVICE_MODE_TX
+#define DEVICE_MODE_RX
 
-#define FEATURE_TX_OLED
-// #define FORCE_TX_WITHOUT_INPUT
+// #define FEATURE_TX_OLED
+#define FORCE_TX_WITHOUT_INPUT
 
-// #define DEBUG_SERIAL
+#define DEBUG_SERIAL
 // #define DEBUG_PING_PONG
 // #define DEBUG_LED
 
@@ -263,10 +263,14 @@ void loop(void)
 {
 
     if (radioState.bytesToRead != NO_DATA_TO_READ) {
+        static uint8_t tmpBuffer[20];
+
+        LoRa.read(tmpBuffer, radioState.bytesToRead);
 
         for (int i = 0; i < radioState.bytesToRead; i++) {
-            qspDecodeIncomingFrame(&qsp, LoRa.fastRead(), &rxDeviceState, &txDeviceState, &radioState);            
+            qspDecodeIncomingFrame(&qsp, tmpBuffer[i], &rxDeviceState, &txDeviceState, &radioState);            
         }
+        
         radioState.rssi = getRadioRssi();
         radioState.snr = getRadioSnr();
 
diff --git a/lora.cpp b/lora.cpp
index 9ccb8d6..80b867e 100644
--- a/lora.cpp
+++ b/lora.cpp
@@ -208,12 +208,17 @@ float LoRaClass::packetSnr()
   return ((int8_t)readRegister(REG_PKT_SNR_VALUE)) * 0.25;
 }
 
-size_t LoRaClass::write(uint8_t byte)
+void LoRaClass::write(uint8_t data)
 {
-  return write(&byte, sizeof(byte));
+  int currentLength = readRegister(REG_PAYLOAD_LENGTH);
+
+  writeRegister(REG_FIFO, data);
+
+  // update length
+  writeRegister(REG_PAYLOAD_LENGTH, currentLength + 1);
 }
 
-size_t LoRaClass::write(const uint8_t *buffer, size_t size)
+void LoRaClass::write(uint8_t buffer[], size_t size)
 {
   int currentLength = readRegister(REG_PAYLOAD_LENGTH);
 
@@ -222,15 +227,10 @@ size_t LoRaClass::write(const uint8_t *buffer, size_t size)
     size = MAX_PKT_LENGTH - currentLength;
   }
 
-  // write data
-  for (size_t i = 0; i < size; i++) {
-    writeRegister(REG_FIFO, buffer[i]);
-  }
+  writeRegister(REG_FIFO, buffer, size);
 
   // update length
   writeRegister(REG_PAYLOAD_LENGTH, currentLength + size);
-
-  return size;
 }
 
 int LoRaClass::available()
@@ -244,6 +244,11 @@ int LoRaClass::fastRead() {
   return readRegister(REG_FIFO);
 }
 
+void LoRaClass::read(uint8_t buffer[], uint8_t size) {
+  _packetIndex += size;
+  return readRegister(REG_FIFO, buffer, size);
+}
+
 int LoRaClass::read()
 {
   if (!available()) {
@@ -498,6 +503,29 @@ uint8_t LoRaClass::singleTransfer(uint8_t address, uint8_t value)
   return response;
 }
 
+void LoRaClass::writeRegister(uint8_t address, uint8_t buffer[], size_t size)
+{
+  bufferTransfer(address | 0x80, buffer, size);
+}
+
+void LoRaClass::readRegister(uint8_t address, uint8_t buffer[], size_t size)
+{
+  bufferTransfer(address & 0x7f, buffer, size);
+}
+
+void LoRaClass::bufferTransfer(uint8_t address, uint8_t buffer[], uint8_t size) {
+  uint8_t response;
+  
+  digitalWrite(_ss, LOW);
+
+  SPI.beginTransaction(_spiSettings);
+  SPI.transfer(address);
+  SPI.transfer(buffer, size);
+  SPI.endTransaction();
+
+  digitalWrite(_ss, HIGH); 
+}
+
 void LoRaClass::onDio0Rise()
 {
   LoRa.handleDio0Rise();
diff --git a/lora.h b/lora.h
index 2c237dd..17ca80d 100644
--- a/lora.h
+++ b/lora.h
@@ -30,11 +30,12 @@ public:
   int packetRssi();
   float packetSnr();
 
-  size_t write(uint8_t byte);
-  size_t write(const uint8_t *buffer, size_t size);
+  void write(uint8_t byte);
+  void write(uint8_t buffer[], size_t size);
   int available();
   int read();
   int fastRead();
+  void read(uint8_t buffer[], uint8_t size);
 
   void onReceive(void(*callback)(int));
 
@@ -69,6 +70,10 @@ private:
   void writeRegister(uint8_t address, uint8_t value);
   uint8_t singleTransfer(uint8_t address, uint8_t value);
 
+  void readRegister(uint8_t address, uint8_t buffer[], size_t size);
+  void writeRegister(uint8_t address, uint8_t buffer[], size_t size);
+  void bufferTransfer(uint8_t address, uint8_t buffer[], uint8_t size);
+
   static void onDio0Rise();
 
 private: