lora: Add example

Signed-off-by: Francois Berder <francois.berder@imgtec.com>

Author: francois-berder

examples/lora_example.py

@@ -0,0 +1,64 @@
+#!/usr/bin/env python3
+"""This example shows how to use the Lora Click wrapper of the LetMeCreate to
+send or receive data.
+
+Depending on the mode selected, it either continuously sends a message every
+second, or it waits for data and prints what it receives.
+The user has to interrupt the program to exit it by pressing Ctrl+C.
+
+To run the example in send mode:
+$ ./lora_example.py s
+
+To run the example in receive mode:
+$ ./lora_example.py r
+
+The Lora Click must be inserted in Mikrobus 1 before running this program.
+"""
+
+from letmecreate.core.common import MIKROBUS_1
+from letmecreate.click import lora
+from letmecreate.core import uart
+from letmecreate.core.uart import UART_BD_57600
+from time import sleep
+import sys
+
+def receive():
+    buffer = lora.receive(16)
+    buffer = bytes(buffer).decode('utf-8')
+    print(buffer)
+
+def send(n):
+    buffer = 'Hello, World! {}'.format(n)
+    lora.send(buffer.encode('utf-8'))
+    print(buffer)
+
+if len(sys.argv) < 2:
+    print('{} (r|s)'.format(sys.argv[0]))
+    sys.exit(-1)
+
+mode = sys.argv[1]
+if mode != 'r' and mode != 's':
+    print('Invalid mode.')
+    sys.exit(-1)
+
+print('Press Ctrl+C to exit program')
+
+uart.init()
+uart.select_bus(MIKROBUS_1)
+uart.set_baudrate(UART_BD_57600)
+
+config = lora.get_default_configuration()
+lora.init(MIKROBUS_1, config)
+
+n = 0
+while True:
+    if mode == 's':
+        send(n)
+        sleep(1)
+    elif mode == 'r':
+        receive()
+
+    n += 1
+
+
+uart.release()