From 92364617d385407c1b883d22d316a641bd27ca81 Mon Sep 17 00:00:00 2001
From: spirkelmann <simon.pirkelmann@gmail.com>
Date: Wed, 20 Nov 2019 18:24:28 +0100
Subject: [PATCH] created LoRaTransceiver class for easier use of LoRa module

---
 micropython/boot.py                     |  0
 micropython/lora_transceiver.py         | 78 +++++++++++++++++++++++++
 micropython/uPyLora/controller_esp32.py |  2 +-
 micropython/uPyLora/sx127x.py           | 23 +++++---
 4 files changed, 93 insertions(+), 10 deletions(-)
 create mode 100644 micropython/boot.py
 create mode 100644 micropython/lora_transceiver.py

diff --git a/micropython/boot.py b/micropython/boot.py
new file mode 100644
index 0000000..e69de29
diff --git a/micropython/lora_transceiver.py b/micropython/lora_transceiver.py
new file mode 100644
index 0000000..e19243e
--- /dev/null
+++ b/micropython/lora_transceiver.py
@@ -0,0 +1,78 @@
+from uPyLora import config_lora
+from uPyLora.sx127x import SX127x
+from uPyLora.controller_esp32 import ESP32Controller
+
+class LoRaTransceiver:
+    def __init__(self, spreadingfactor=9, bandwidth=125E3, frequency=868E6, syncword=0x12, display=None):
+        # set up radio module
+        # SX127x LoRa module configured for LoRaWAN Channel 0
+        self.controller = ESP32Controller()
+        self.lora = self.controller.add_transceiver(SX127x(name='LoRa'), pin_id_ss=ESP32Controller.PIN_ID_FOR_LORA_SS, pin_id_RxDone=ESP32Controller.PIN_ID_FOR_LORA_DIO0)
+
+        self.setSpreadingFactor(spreadingfactor)
+        self.setSignalBandwidth(bandwidth) 
+        self.setFrequency(frequency)
+        self.setSyncWord(syncword)
+
+        self.display = display
+
+    def setSpreadingFactor(self, spreadingfactor):
+        """ set spreading factor 
+            possible values are  7-12 
+        """
+        self.lora.setSpreadingFactor(spreadingfactor)
+    
+    def setFrequency(self, frequency):
+        """ set frequency (= channel used) 
+            for now only 868 Mhz and 868.1 MHz are supported
+        """
+        self.lora.setFrequency(frequency)
+
+    def setSignalBandwidth(self, bandwidth):
+        """ set the bandwidth 
+            possible values should be 125 or 250 kHz according to EU 868 frequency plan
+        """
+        self.lora.setSignalBandwidth(bandwidth)
+
+    def setSyncWord(self, syncword):
+        """ set the sync word 
+            should be 0x12 for plain LoRa and 0x34 for LoRaWAN
+        """
+        self.lora.setSyncWord(syncword)
+
+    def send(self, data):
+        """ send raw data 
+        """
+        print("Sending {}".format(data))
+        self.lora.println_raw(data)
+
+        if self.display is not None:
+            self.display.show_text_wrap("Message {} sent.".format(data))
+    
+    def send_string(self, message):
+        """ send a message 
+            message should be a string
+        """
+        print("Sending {}".format(message))
+        self.lora.println(message)
+
+        if self.display is not None:
+            self.display.show_text_wrap("Message {} sent.".format(message))
+
+    def recv(self):
+        """ start listening for messages and output them on the console """
+        if self.display is not None:
+            self.display.show_text_wrap("Receiving ...")
+
+        while True:
+            # check for new message
+            if self.lora.receivedPacket():
+                self.lora.blink_led()
+
+                try:
+                    payload = self.lora.read_payload()
+                    if self.display is not None: 
+                        self.display.show_text_wrap("Received: {0} RSSI: {1}".format(payload.decode(), lora.packetRssi()))
+
+                except Exception as e:
+                    print(e)
diff --git a/micropython/uPyLora/controller_esp32.py b/micropython/uPyLora/controller_esp32.py
index 33a0fca..30032fa 100644
--- a/micropython/uPyLora/controller_esp32.py
+++ b/micropython/uPyLora/controller_esp32.py
@@ -1,5 +1,5 @@
 from machine import Pin, SPI, reset
-from controller import Controller
+from .controller import Controller
 
 
 class ESP32Controller(Controller):
diff --git a/micropython/uPyLora/sx127x.py b/micropython/uPyLora/sx127x.py
index add11b0..8ad68b5 100644
--- a/micropython/uPyLora/sx127x.py
+++ b/micropython/uPyLora/sx127x.py
@@ -174,13 +174,9 @@ class SX127x:
 
 
     def println(self, string, implicitHeader = False):
-        self.aquire_lock(True)  # wait until RX_Done, lock and begin writing.
-
-        self.beginPacket(implicitHeader)
-        self.write(string.encode())
-        self.endPacket()
-
-        self.aquire_lock(False) # unlock when done writing
+        """ function for sending string data
+        """
+        self.println_raw(string.encode(), implicitHeader)
 
     def println_raw(self, data, implicitHeader = False):
         """ function for sending raw binary data 
@@ -394,7 +390,10 @@ class SX127x:
             self.writeRegister(REG_OP_MODE, MODE_LONG_RANGE_MODE | MODE_RX_SINGLE)
 
 
-    def read_payload(self):
+    def read_payload_raw(self):
+        """ get the payload of the most recent message 
+            this function returns the payload data as a bytearray
+        """
         # set FIFO address to current RX address
         # fifo_rx_current_addr = self.readRegister(REG_FIFO_RX_CURRENT_ADDR)
         self.writeRegister(REG_FIFO_ADDR_PTR, self.readRegister(REG_FIFO_RX_CURRENT_ADDR))
@@ -408,7 +407,13 @@ class SX127x:
             payload.append(self.readRegister(REG_FIFO))
 
         self.collect_garbage()
-        return bytes(payload)
+        return payload
+
+    def read_payload(self): 
+        """ get the payload of the most recent message 
+            this function returns the payload data as a bytes (i.e. a printable string)
+        """
+        return bytes(self.read_payload_raw())
 
     def printTemperature(self):
         # only work if LoRa mode is off