Impulse 463E - Manual (Page 76)

© Sealevel Systems, Inc. - 73 - SeaI/O User Manual
IOCTL Calls and Functionality
The Ioctl method allows multiple functions to be implemented through a single,
convienient call. The last parameter of all Ioctl calls is a void pointer – a pointer that
is cast to a particular data type depending on the use of the Ioctl call. Likewise, the
actual Modbus traffic generated depends on the ‘which’ parameter and the type of
Ioctl functionality desired. The following is a list of the Ioctl call types and their
functionality.
Read Module Communications Parameters
Which IOCTL_READ_COMM_PARAM (1)
Description Reads the communication parameter, model specific information,
and configuration data from the SeaIO module.
The last parameter is expected to be a pointer to a ‘seaio_ioctl_s’
structure. This structure will be populated with relavent
information regarding the module mode, bridge type, baud rate,
parity.
All the returned information is stored in the ‘seaio_ioctl_s’
structure as a union named ‘params’.
Models All SeaIO modules
Expected
Data Type Pointer to a seaio_ioctl_s structure
Return Codes None