MODBUS_RTU_SET_SERIA(3) Libmodbus Manual MODBUS_RTU_SET_SERIA(3)NAME
modbus_rtu_set_serial_mode - set the serial mode
SYNOPSIS
int modbus_rtu_set_serial_mode(modbus_t *ctx);
DESCRIPTION
The modbus_rtu_set_serial_mode() function shall set the selected serial mode:
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 supported on Linux kernels 2.6.28 onwards.
RETURN VALUE
The modbus_set_serial_mode() function shall return 0 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.
ENOTSUP
The function is not supported on your platform.
If the call to ioctl() fails, the error code of ioctl will be returned.
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_SET_SERIA(3)
Check Out this Related Man Page
MODBUS_REPLY_EXCEPTI(3) Libmodbus Manual MODBUS_REPLY_EXCEPTI(3)NAME
modbus_reply_exception - send an exception reponse
SYNOPSIS
*int modbus_reply_exception(modbus_t *ctx, const uint8_t *req, unsigned int exception_code);
DESCRIPTION
The modbus_reply_exception() function shall send an exception response based on the exception_code in argument.
The libmodbus provides the following exception codes:
o MODBUS_EXCEPTION_ILLEGAL_FUNCTION (1)
o MODBUS_EXCEPTION_ILLEGAL_DATA_ADDRESS (2)
o MODBUS_EXCEPTION_ILLEGAL_DATA_VALUE (3)
o MODBUS_EXCEPTION_SLAVE_OR_SERVER_FAILURE (4)
o MODBUS_EXCEPTION_ACKNOWLEDGE (5)
o MODBUS_EXCEPTION_SLAVE_OR_SERVER_BUSY (6)
o MODBUS_EXCEPTION_NEGATIVE_ACKNOWLEDGE (7)
o MODBUS_EXCEPTION_MEMORY_PARITY (8)
o MODBUS_EXCEPTION_NOT_DEFINED (9)
o MODBUS_EXCEPTION_GATEWAY_PATH (10)
o MODBUS_EXCEPTION_GATEWAY_TARGET (11)
The initial request req is required to build a valid response.
RETURN VALUE
The modbus_reply_exception() function shall return the length of the response sent if successful. Otherwise it shall return -1 and set
errno.
ERRORS
EINVAL
The exception code is invalid
SEE ALSO modbus_reply(3)libmodbus(7)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_REPLY_EXCEPTI(3)
Need help for RS232 communication with switches in order to optimise the data traffic. How to manipulate different flags in termios struct to do the same? (1 Reply)
Hi,
I am working on serial communication on Unix. Can anyone guide me through it. The steps required for RS 232 communication and can i do serial communication even if i dont have super user previledges.
Thankx,
Vicky (1 Reply)
How and where can I read definition of such terms in unix ? There is a manual on Unix. How can one access it ?
--
Sven-Brussels
GSM: +32 (0)485/389679
OSX.1.1.5-EntX:iBook-PowerPC G3 500Mhz/128MBRam-AZERTY-Keyboard (1 Reply)
I have software running under AIX 5.3 that should communicate with a special device using standard communication protocol (Modbus) using serial RS-232 line
The settings are correct in both sides, But I can't establish a connection.
I suspect that there's something that I should do regarding the... (3 Replies)
Hi,
I have tried to setup the console on a Power5 9131-52A type IBM Server. On the back there are 2 RS-232 ports labeled T1 T2. I am going under the assuming that these are the serial ports (Normally the serial ports are S1 S0). When I finish assigning the console under smit, I get no response... (3 Replies)
Thanks a lot first of all Corona688 for being extremely patient with all my queries and answer them as simply as possible. Now I am thinking of starting a new thread about Serial ports, but before that I am asking for some reading material on serial ports and terminal devices. So that when I come... (7 Replies)