table of contents
MODBUS_RTU_GET_SERIA(3) | Libmodbus Manual | MODBUS_RTU_GET_SERIA(3) |
NAME¶
modbus_rtu_get_serial_mode - get the current serial modeSYNOPSIS¶
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_RS232the 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.
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¶
EINVALThe current libmodbus backend is not
RTU.
AUTHORS¶
The libmodbus documentation was written by Stéphane Raimbault < stephane.raimbault@gmail.com[1]>NOTES¶
- 1.
- stephane.raimbault@gmail.com
mailto:stephane.raimbault@gmail.com
05/26/2012 | libmodbus 3.0.3 |