modbus_read_input_registers(3) [debian man page]

MODBUS_READ_INPUT_RE(3) 					 Libmodbus Manual					   MODBUS_READ_INPUT_RE(3)

NAME

       modbus_read_input_registers - read many input registers

SYNOPSIS

       int modbus_read_input_registers(modbus_t *ctx, int addr, int nb, uint16_t *dest);

DESCRIPTION

       The modbus_read_input_registers() function shall read the content of the nb input registers to address addr of the remote device. The
       result of the reading is stored in dest array as word values (16 bits).

       You must take care to allocate enough memory to store the results in dest (at least nb * sizeof(uint16_t)).

       The function uses the Modbus function code 0x04 (read input registers). The holding registers and input registers have different historical
       meaning, but nowadays it's more common to use holding registers only.

RETURN VALUE

       The modbus_read_input_registers() function shall return the number of read input registers if successful. Otherwise it shall return -1 and
       set errno.

ERRORS

       EMBMDATA
	   Too many bits requested

SEE ALSO

       modbus_read_input_bits(3) modbus_write_register(3) modbus_write_registers(3)

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_READ_INPUT_RE(3)

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)