Static variables in ModbusCommonLoad - Manual - SIMATIC AX - Instructions that can be used for Modbus-RTU communication. - Siemens.Simatic.S71500.CommunicationsProcessor.ModbusRtu,library

Siemens.Simatic.S71500.CommunicationsProcessor.ModbusRtu library
Portfolio
SIMATIC AX
Product
SIMATIC AX
Software version
1.0.2
Edition
11/2024
Language
English (original)
Package Name
@ax/simatic-1500-modbusrtu

This table below shows the public static variables in the instance of ModbusCommonLoad that you can use in your program.

Variable Data type Default Description
ICHAR_GAP WORD WORD#0 Maximum character delay time between characters. This parameter is specified in milliseconds and increases the anticipated period between the received characters. The corresponding number of bit times for this parameter is added to the Modbus default value of 35 bit times (3.5 character times).
RETRIES WORD WORD#2 Number of retries that the master executes before the error code 0x80C8 for "No response" is returned.
EN_SUPPLY_VOLT BOOL FALSE Enable diagnostics for missing supply voltage L+
MODE USINT USINT#4 Operating mode
Valid operating modes are:
  • 0 = Full duplex (RS232)
  • 1 = Full duplex (RS422) four-wire mode (point-to-point)
  • 2 = Full duplex (RS 422) four-wire mode (multipoint master, CM PtP (ET 200SP))
  • 3 = Full duplex (RS 422) four-wire mode (multipoint slave, CM PtP (ET 200SP))
  • 4 = Half duplex (RS485) two-wire mode 1)
LINE_PRE USINT USINT#0 Receive line initial state
Valid initial states are:
  • 0 = "No" initial state 1)
  • 1 = signal R(A)=5 V, signal R(B)=0 V (break detection):
    Break detection is possible with this initial state.
    Can only be selected with: "Full duplex (RS422) four-wire operation (point-to-point connection)" and "Full duplex (RS422) four-wire mode (multipoint slave)".
  • 2 = signal R(A)=0 V, signal R(B)=5 V:
    This default setting corresponds to the idle state (no active send operation). No break detection is possible with this initial state.
BRK_DET USINT USINT#0 Break detection
The following are valid:
  • 0 = break detection deactivated
  • 1 = break detection activated
EN_DIAG_ALARM BOOL FALSE Activate diagnostics interrupt:
  • 0 - not activated
  • 1 - activated
STOP_BITS USINT USINT#1 Number of stop bits;
  • 1 = 1 stop bit,
  • 2 = 2 stop bits,
  • 0, 3 to 255 = reserved

1) Required setting for the use of PROFIBUS cables with CM 1241 for RS485