1 files changed, 109 insertions, 0 deletions
diff --git a/tools/reset_leonardo.py b/tools/reset_leonardo.py
new file mode 100644
index 0000000..be53aa1
--- /dev/null
+++ b/tools/reset_leonardo.py
@@ -0,0 +1,109 @@
+"""Tool used to reset a Arduino Leonardo board."""
+from os import O_NDELAY, O_NOCTTY, O_RDWR, open as os_open, close as os_close
+import sys
+from termios import (
+    B1200,
+    TCSANOW,
+    TIOCM_DTR,
+    TIOCM_RTS,
+    TIOCMBIC,
+    TIOCMBIS,
+    tcgetattr,
+    tcsetattr
+)
+from fcntl import ioctl
+from argparse import ArgumentParser
+from dataclasses import dataclass
+from pathlib import Path
+from struct import pack
+from time import sleep
+
+
+@dataclass
+class ParsedArguments:
+    """Parsed command-line arguments."""
+    serial_port: Path
+
+
+class TTYAttributes:
+    """TTY attributes."""
+
+    def __init__(self, tty_fd: int):
+        """Initializes the TTY attributes."""
+        self.__tty_fd = tty_fd
+        self.__attrs = tcgetattr(tty_fd)
+
+    @property
+    def ispeed(self):
+        """The ispeed."""
+        return self.__attrs[4]
+
+    @ispeed.setter
+    def ispeed(self, ispeed: int):
+        self.__attrs[4] = ispeed
+
+    @property
+    def ospeed(self):
+        """The ospeed."""
+        return self.__attrs[5]
+
+    @ospeed.setter
+    def ospeed(self, ospeed: int):
+        self.__attrs[5] = ospeed
+
+    def set(self):
+        """Sets the TTY attributes."""
+        tcsetattr(self.__tty_fd, TCSANOW, self.__attrs)
+
+
+RESET_BAUD_RATE = B1200
+
+DESCRIPTION = "Tool used to reset a Arduino Leonardo board."
+
+
+def main():
+    """Main."""
+    parser = ArgumentParser(allow_abbrev=False, description=DESCRIPTION)
+
+    parser.add_argument(
+        "serial_port",
+        type=Path,
+        help="The serial port for a Arduino Leonardo board"
+    )
+
+    arguments = parser.parse_args(namespace=ParsedArguments)
+
+    is_serial_port_char_device = arguments.serial_port.is_char_device()
+
+    # Verify that the serial port exists
+    if not arguments.serial_port.is_file() and not is_serial_port_char_device:
+        print("Error: The serial port file doesn't exist")
+        sys.exit(1)
+
+    # Verify that the serial port is a character device
+    if not is_serial_port_char_device:
+        print("Error: The serial port file is not a character device")
+        sys.exit(1)
+
+    serial_port_fd = os_open(
+        str(arguments.serial_port),
+        O_RDWR | O_NOCTTY | O_NDELAY
+    )
+
+    tty_attributes = TTYAttributes(serial_port_fd)
+
+    tty_attributes.ispeed = RESET_BAUD_RATE
+    tty_attributes.ospeed = RESET_BAUD_RATE
+
+    tty_attributes.set()
+
+    ioctl(serial_port_fd, TIOCMBIS, pack("I", TIOCM_RTS))
+    ioctl(serial_port_fd, TIOCMBIC, pack("I", TIOCM_DTR))
+
+    os_close(serial_port_fd)
+
+    sleep(1.98)
+
+
+if __name__ == "__main__":
+    main()