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Release Notes
PLCIO V4.5 (2015) PLCIO V4.4 (2013) PLCIO V4.3 (2011) PLCIO V4.2 (2009) PLCIO V4.1 (2007) PLCIO V4.0 (2005)

PLCIO 4.1 Release Notes

New Features

Remote Processing:

PLCIO now has built-in support for solicited communication with PLCs connected to remote computers over the ethernet. The new concentrator daemon, `plciod', forwards PLCIO requests from multiple applications to a single PLC in a round-robin fashion. Programs that were previously unable to share the same connection to a single PLC can now do so through the `remote' module.

Microsoft Windows Support:

PLCIO can now run on any Windows operating system version Windows 95 or later. Compiling PLCIO for Windows requires the MSYS/MinGW environment and a recent GCC compiler. Details can be found at

Other Features:

- Added "j_fileno" to the PLCSLAVE structure for Allen-Bradley file number retrieval.

- The PLCIO configuration file, plcio.cfg, now allows the keyword NULL to be present in the point configuration field. This lets users define a soft PLC but still use physical PLC addresses.

- Added two new keywords, PLC_LOG_NONE and PLC_LOG_TTY, that can be used as the argument to plc_log_init(). PLC_LOG_NONE is an alias for NULL, meaning to turn off all logging. PLC_LOG_TTY is an alias for the current terminal running the program.

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