read100.py

# -*- coding: utf_8 -*-

import serial

import modbus_tk
import modbus_tk.defines as cst
from modbus_tk import modbus_rtu

#PORT = 1
PORT = '/dev/ttyUSB1'

def main():
    """main"""
    logger = modbus_tk.utils.create_logger("console")

    try:
        #Connect to the slave
        master = modbus_rtu.RtuMaster(
            serial.Serial(port=PORT, baudrate=115200, bytesize=8, parity='N', stopbits=1, xonxoff=0)
        )
        master.set_timeout(1.0)
        master.set_verbose(True)
        logger.info("connected")
	while 1:
	    try:
        	logger.info(master.execute(7, cst.READ_HOLDING_REGISTERS, 40960, 100))
		logger.info(master.execute(1, cst.READ_HOLDING_REGISTERS, 40960, 100))
		logger.info(master.execute(23, cst.READ_HOLDING_REGISTERS, 100, 20))
                logger.info(master.execute(24, cst.READ_HOLDING_REGISTERS, 100, 20))
	    except:
		print "smth is wrong!!!"
        #send some queries
        #logger.info(master.execute(1, cst.READ_COILS, 0, 10))
        #logger.info(master.execute(1, cst.READ_DISCRETE_INPUTS, 0, 8))
        #logger.info(master.execute(1, cst.READ_INPUT_REGISTERS, 100, 3))
        #logger.info(master.execute(1, cst.READ_HOLDING_REGISTERS, 100, 12))
        #logger.info(master.execute(1, cst.WRITE_SINGLE_COIL, 7, output_value=1))
        #logger.info(master.execute(1, cst.WRITE_SINGLE_REGISTER, 100, output_value=54))
        #logger.info(master.execute(1, cst.WRITE_MULTIPLE_COILS, 0, output_value=[1, 1, 0, 1, 1, 0, 1, 1]))
        #logger.info(master.execute(1, cst.WRITE_MULTIPLE_REGISTERS, 100, output_value=xrange(12)))

    except modbus_tk.modbus.ModbusError as exc:
        logger.error("%s- Code=%d", exc, exc.get_exception_code())

if __name__ == "__main__":
    main()