Add circuit pass-through

Author: LeStarch

circuit-python-lora-passthrough/boot.py

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+import usb_cdc
+usb_cdc.enable(console=True, data=True)

circuit-python-lora-passthrough/code.py

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+"""
+CircuitPython Feather RP2350 LoRa Radio forwarder
+
+This code will forward any received LoRa packets to the serial console (sys.stdout). It cycles through neo pixel colors
+to indicate packet reception.
+"""
+import time
+import board
+import digitalio
+import adafruit_rfm9x
+import usb_cdc
+
+# Radio constants
+RADIO_FREQ_MHZ = 437.4
+CS = digitalio.DigitalInOut(board.SPI0_CS0)
+RESET = digitalio.DigitalInOut(board.RF1_RST)
+
+rfm95 = adafruit_rfm9x.RFM9x(board.SPI(), CS, RESET, RADIO_FREQ_MHZ)
+rfm95.spreading_factor = 8
+rfm95.signal_bandwidth = 125000
+rfm95.coding_rate = 5
+rfm95.preamble_length = 8
+time_start = time.time()
+packet_count = 0
+print("[INFO] LoRa Receiver receiving packets")
+while True:
+    # Look for a new packet - wait up to 2 seconds:
+    packet = rfm95.receive(timeout=2.0)
+    # If no packet was received during the timeout then None is returned.
+    if packet is not None:
+        usb_cdc.data.write(packet)
+        packet_count += 1
+    time_delta = time.time() - time_start
+    if time_delta > 10:
+        print(f"[INFO] Packets received: {packet_count}")
+        time_start = time.time()
+    data = usb_cdc.data.read(usb_cdc.data.in_waiting)
+    if len(data) > 0:
+        rfm95.send(data)