Feat: add ESP32 bridge functionality and physical switch control

pc_reader.py

@@ -55,17 +55,41 @@ def keyboard_control(ser):
 
 
 def main():
+    import time
+
     parser = argparse.ArgumentParser()
-    parser.add_argument("port", help="ESP32 serial port, for example COM5")
-    parser.add_argument("--baud", type=int, default=230400)
+    parser.add_argument("port", help="ESP32 serial port, for example /dev/ttyUSB0")
+    parser.add_argument("--baud", type=int, default=115200)
     args = parser.parse_args()
 
     buffer = bytearray()
     packet_count = 0
     last_time_ms = None
 
-    with serial.Serial(args.port, args.baud, timeout=1) as ser:
+    ser = serial.Serial()
+    ser.port = args.port
+    ser.baudrate = args.baud
+    ser.timeout = 0.05
+    ser.write_timeout = 0.05
+
+    # Avoid unwanted ESP32 auto-reset / boot-mode toggling.
+    ser.dtr = False
+    ser.rts = False
+
+    ser.open()
+
+    try:
+        # Some USB-UART adapters change line states during open().
+        ser.dtr = False
+        ser.rts = False
+
+        ser.reset_input_buffer()
+        ser.reset_output_buffer()
+
         print("Reading {} at {} baud".format(args.port, args.baud))
+        print("Waiting for ESP32 main.py startup...")
+        time.sleep(4.0)
+
         threading.Thread(
             target=keyboard_control,
             args=(ser,),
@@ -82,12 +106,15 @@ def main():
                 if sync_index < 0:
                     del buffer[:-1]
                     break
+
                 if sync_index:
                     del buffer[:sync_index]
+
                 if len(buffer) < PACKET_SIZE:
                     break
 
                 packet = bytes(buffer[:PACKET_SIZE])
+
                 if (sum(packet[:-1]) & 0xFF) != packet[-1]:
                     del buffer[0]
                     continue
@@ -101,6 +128,7 @@ def main():
                 else:
                     delta = (data["t_ms"] - last_time_ms) & 0xFFFFFFFF
                     frequency = 1000.0 / delta if delta else 0.0
+
                 last_time_ms = data["t_ms"]
 
                 print(
@@ -116,6 +144,9 @@ def main():
                     )
                 )
 
+    finally:
+        ser.close()
+
 
 if __name__ == "__main__":
     main()