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 modbus_rtu_get_serial_mode() 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 Stephane Raimbault <stephane.raimbault@gmail.com[1]>

NOTES

	1. stephane.raimbault@gmail.com
	   mailto:stephane.raimbault@gmail.com

libmodbus 3.0.3 						    05/26/2012						   MODBUS_RTU_GET_SERIA(3)