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Impulse 463E User Manual

Page 70

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© Sealevel Systems, Inc.

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SeaI/O User Manual

Write

CSeaMaxW32::Write( slave_address_t slaveID, seaio_type_t type, address_loc_t

starting_address, address_range_t range, unsigned char*
data)

Description

Write performs a Modbus write on an opened SeaIO module and
returns the data by reference.

The actual Modbus write type is specified by the ‘type’ argument.
Since Modbus is actually base one, the starting location should be
no less than one. Likewise, the range indicates how many
consecutive inputs should be read.

The final parameter, ‘data’, is a pointer to a buffer in which to
store the returned data – specifically, an array of bytes. Consult
the provided code examples for model specific information.

Parameters

slave_address_t slave_id

seaio_type_t type

address_loc_t starting_address

address_range_t range

unsigned char* data

Return Codes

-14

EFAULT

A Modbus read exception has occurred – the
first byte of the data buffer contains the
exception code.

-22

EINVAL

A NULL pointer has been supplied where a
pointer to a data buffer was expected.

-9

EBADF

The specified communication is not currently
established.

-18

EXDEV

Can not write data to the outbound
connection – connection error.

-19

ENODEV The SeaIO module did not respond.

-34

ERANGE Attempting to write to more IO points than

are available.

-27 EFBIG Illegal

data

value

≥ 0

Success – The number of valid data bytes in
the buffer.