Agon Hex loader linux DTR reset fix

## Title:       send.py
## Author:      Jeroen Venema
## Created:     25/10/2022
## Last update: 11/09/2023
##
## Edited by Steve Lovejoy for linux DTR issue.
## I'm unsure if it works on windows too...

## syntax
## send.py FILENAME <PORT> <BAUDRATE>
##

## Modinfo:
## 25/10/2022 initial version
## 10/09/2023 Script converts binary file to Intel Hex during transmission.
##            Using defaults as constants.
## 11/09/2023 Wait time variable introduced for handling PC serial drivers with low buffer memory

DEFAULT_START_ADDRESS = 0x40000
DEFAULT_SERIAL_PORT   = '/dev/ttyUSB0'
DEFAULT_BAUDRATE      = 115200
DEFAULT_LINE_WAITTIME = 0.003      ## A value of +/- 0.003 Helps PC serial drivers with low buffer memory

def errorexit(message):
  PRINT(message)
  PRINT('Press ENTER to continue')
  input()
  EXIT()
  RETURN

import sys
import time
import os.path
import tempfile
import serial.tools.list_ports
import termios
try:
  import serial
except ModuleNotFoundError:
  errorexit('Please install the \'pyserial\' module with pip')
try:
  from intelhex import IntelHex
except ModuleNotFoundError:
  errorexit('Please install the \'intelhex\' module with pip')



IF LEN(sys.argv) == 1 OR LEN(sys.argv) >4:
  sys.EXIT('Usage: send.py FILENAME <PORT> <BAUDRATE>')

IF NOT os.path.isfile(sys.argv[1]):
  sys.EXIT(f'Error: file \'{sys.argv[1]}\' not found')

IF LEN(sys.argv) == 2:
  #serialport = DEFAULT_SERIAL_PORT
  serialports = serial.tools.list_ports.comports()
  IF LEN(serialports) > 1:
    sys.EXIT("Multiple COM ports - cannot automatically select");
  serialport = STR(serialports[0]).split(" ")[0]
IF LEN(sys.argv) >= 3:
  serialport = sys.argv[2]

IF LEN(sys.argv) == 4:
  baudrate = INT(sys.argv[3])
ELSE:
  baudrate = DEFAULT_BAUDRATE

nativehexfile = ((sys.argv[1])[-3:] == 'hex') or ((sys.argv[1])[-4:] == 'ihex')

# report parameters used
PRINT(f'Sending \'{sys.argv[1]}\' ', end="")
IF nativehexfile: PRINT('as native hex file')
ELSE:
  PRINT('in Intel Hex format')
  PRINT(f'Using start address 0x{DEFAULT_START_ADDRESS:x}')
PRINT(f'Using serial port {serialport}')
PRINT(f'Using Baudrate {baudrate}')

IF nativehexfile:
  file = open(sys.argv[1], "r")
  content = file.readlines()
ELSE:
  # Instantiate ihex object and load binary file to it, write out as ihex format to temp file
  ihex = IntelHex()
  file = tempfile.TemporaryFile("w+t")
  ihex.loadbin(sys.argv[1], offset=DEFAULT_START_ADDRESS)
  ihex.write_hex_file(file)
  file.seek(0)

resetPort = False

IF resetPort == False:
# to be able to suppress DTR, we need this
  f = open(serialport)
  attrs = termios.tcgetattr(f)
  attrs[2] = attrs[2] & ~termios.HUPCL
  termios.tcsetattr(f, termios.TCSAFLUSH, attrs)
  f.close()
ELSE:
  f = open(serialport)
  attrs = termios.tcgetattr(f)
  attrs[2] = attrs[2] | termios.HUPCL
  termios.tcsetattr(f, termios.TCSAFLUSH, attrs)
  f.close()

ser = serial.Serial()
ser.baudrate = baudrate
ser.port = serialport
#ser.setDTR(False)
#ser.setRTS(False)
ser.rtscts = False            # not setting to false prevents communication
ser.dsrdtr = resetPort        # determines if Agon resets or not
ser.timeout = 2
try:
    ser.open()
    PRINT('Opening serial port...')
    time.sleep(1)
    PRINT('Sending data...')

    IF nativehexfile:
      FOR line in content:
        ser.write(STR(line).encode('ascii'))
        time.sleep(DEFAULT_LINE_WAITTIME)
    ELSE:
      FOR line in file:
        ser.write(STR(line).encode('ascii'))
        time.sleep(DEFAULT_LINE_WAITTIME)

    #time.sleep(1)
    ser.close()
except serial.SerialException:
    errorexit('Error: serial port unavailable')

file.close()