1"""
  2Controls the USB relay
  3
  4# (c) 2020-2024 TurnAround Factor, Inc.
  5#
  6# CUI DISTRIBUTION CONTROL
  7# Controlled by: DLA J68 R&D SBIP
  8# CUI Category: Small Business Research and Technology
  9# Distribution/Dissemination Controls: PROTECTED BY SBIR DATA RIGHTS
 10# POC: GOV SBIP Program Manager Denise Price, 571-767-0111
 11# Distribution authorized to U.S. Government Agencies only, to protect information not owned by the
 12# U.S. Government and protected by a contractor’s ‘limited rights’ statement, or received with the understanding that
 13# it is not routinely transmitted outside the U.S. Government (determination made September 14, 2024). Other requests
 14# for this document shall be referred to ACOR DLA Logistics Operations (J-68), 8725 John J. Kingman Rd., Suite 4317,
 15# Fort Belvoir, VA 22060-6221
 16#
 17# SBIR DATA RIGHTS
 18# Contract No.:SP4701-23-C-0083
 19# Contractor Name: TurnAround Factor, Inc.
 20# Contractor Address: 10365 Wood Park Ct. Suite 313 / Ashland, VA 23005
 21# Expiration of SBIR Data Rights Period: September 24, 2029
 22# The Government's rights to use, modify, reproduce, release, perform, display, or disclose technical data or computer
 23# software marked with this legend are restricted during the period shown as provided in paragraph (b)(4) of the Rights
 24# in Noncommercial Technical Data and Computer Software--Small Business Innovative Research (SBIR) Program clause
 25# contained in the above identified contract. No restrictions apply after the expiration date shown above. Any
 26# reproduction of technical data, computer software, or portions thereof marked with this legend must also reproduce
 27# the markings.
 28"""
 29
 30import atexit
 31
 32import serial
 33from serial.serialutil import SerialException
 34
 35from hitl_tester.modules.logger import logger
 36
 37
 38# NOTE: Relay Assignments
 39# Relay 0 = Battery #1 Power Switch
 40# Relay 1 = Battery #2 Power Switch
 41# Relay 2 = Battery #3 Power Switch
 42# Relay 3 = N/A
 43
 44
 45class NoDataException(Exception):
 46    """Exception raised when no data is received"""
 47
 48    def __init__(self):
 49        super().__init__("No data received")
 50
 51
 52class RelayController:
 53    """Relay controller"""
 54
 55    @staticmethod
 56    def on(num: int):
 57        """Turn relay on"""
 58        RelayController.call(f"relay on {num}")
 59
 60    @staticmethod
 61    def off(num: int):
 62        """Turn relay off"""
 63        RelayController.call(f"relay off {num}")
 64
 65    @staticmethod
 66    def status():
 67        """Shows relay status"""
 68        relays = []
 69        for i in range(4):
 70            relays.append(RelayController.call(f"relay read {i}"))
 71        print(f"Relay 1: {relays[0]}\nRelay 2: {relays[1]}\nRelay 3: {relays[2]}\nRelay 4: {relays[3]}")
 72
 73    @staticmethod
 74    def call(cmd: str) -> str:
 75        """Talk to relay"""
 76        response = None
 77        try:
 78            # 9600,8,N,1
 79            with serial.Serial("/dev/taf-relay", timeout=1) as ser:
 80                ser.write(bytes(cmd + "\r", "utf-8"))
 81                response = ser.read(25)
 82                if not response:
 83                    raise NoDataException
 84                response = response[len(cmd) : -1]
 85                if not response:
 86                    raise NoDataException
 87                response = response.decode().strip("\n\r")
 88        except (TimeoutError, NoDataException) as ex:
 89            logger.write_debug_to_report(ex)
 90        except (FileNotFoundError, SerialException):
 91            pass
 92        return response or ""
 93
 94    @staticmethod
 95    def reset():
 96        """Reset relay"""
 97        for i in range(3):
 98            RelayController.off(i)
 99
100
101@atexit.register
102def __atexit__():
103    """Open all relays when shutting down."""
104    logger.write_debug_to_report("Shutting down relays.")
105    RelayController.reset()
106
107
108if __name__ == "__main__":
109    print("Resetting relays...")
110    RelayController.reset()
111    print("Status:")
112    RelayController.status()