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MODBUS_RTU_GET_SERIA(3)	       libmodbus Manual	       MODBUS_RTU_GET_SERIA(3)

NAME
       modbus_rtu_get_serial_mode - get	the current serial mode

SYNOPSIS
       int modbus_rtu_get_serial_mode(modbus_t *ctx);

DESCRIPTION
       The modbus_rtu_get_serial_mode()	function shall return the serial mode
       currently used by the libmodbus context:

       MODBUS_RTU_RS232
	   the serial line is set for RS232 communication. RS-232 (Recommended
	   Standard 232) is the	traditional name for a series of standards for
	   serial binary single-ended data and control signals connecting
	   between a DTE (Data Terminal	Equipment) and a DCE (Data
	   Circuit-terminating Equipment). It is commonly used in computer
	   serial ports

       MODBUS_RTU_RS485
	   the serial line is set for RS485 communication. EIA-485, also known
	   as TIA/EIA-485 or RS-485, is	a standard defining the	electrical
	   characteristics of drivers and receivers for	use in balanced
	   digital multipoint systems. This standard is	widely used for
	   communications in industrial	automation because it can be used
	   effectively over long distances and in electrically noisy
	   environments.

       This function is	only available on Linux	kernels	2.6.28 onwards and can
       only be used with a context using a RTU backend.

RETURN VALUE
       The function shall return MODBUS_RTU_RS232 or MODBUS_RTU_RS485 if
       successful. Otherwise it	shall return -1	and set	errno to one of	the
       values defined below.

ERRORS
       EINVAL
	   The current libmodbus backend is not	RTU.

AUTHORS
       The libmodbus documentation was written by StA(C)phane Raimbault
       <stephane.raimbault@gmail.com>

libmodbus v3.1.6		  08/10/2020	       MODBUS_RTU_GET_SERIA(3)

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | AUTHORS

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