Added libmodbus

libmodbus_src/AUTHORS

@@ -0,0 +1,8 @@
+Stéphane Raimbault <[email protected]>
+Tobias Doerffel <[email protected]> - CLA
+Florian Forster <[email protected]>
+oldfaber <[email protected]>
+Hannu Vuolasaho <[email protected]> - CLA
+Michael Heimpold <[email protected]> - CLA
+Jimmy Bergström <[email protected]> - CLA
+Jakob Bysewski <[email protected]> - CLA

libmodbus_src/CONTRIBUTING.md

@@ -0,0 +1,29 @@
+How Do I Submit A Good Bug Report?
+----------------------------------
+
+Please, don't send direct emails to Stéphane Raimbault unless you want
+commercial support.
+
+Take care to read the documentation at http://libmodbus.org/documentation/.
+
+- *Be sure it's a bug before creating an issue*, in doubt, post a message on
+  https://groups.google.com/forum/#!forum/libmodbus or send an email to
+  [email protected]
+
+- *Use a clear and decriptive title* for the issue to identify
+
+- *Which version of libmodbus are you using?* you can obtain this information
+from your package manager or by running `pkg-config --modversion libmodbus`.
+You can provide the sha1 of the commit if you have fetched the code with `git`.
+
+- *Which operating system are you using?*
+
+- *Describe the exact steps which reproduce the problem* in as many details as
+possible. For example, the software/equipement which runs the Modbus server, how
+the clients are connected (TCP, RTU, ASCII) and the source code you are using.
+
+- *Enable the debug mode*, libmodbus provides a function to display the content
+of the Modbus messages and it's very convenient to analyze issues
+(http://libmodbus.org/docs/latest/modbus_set_debug.html).
+
+Good bug reports provide right and quick fixes!

libmodbus_src/ISSUE_TEMPLATE.md

@@ -0,0 +1,13 @@
+### libmodbus version
+
+### Operating system
+
+### Description of the Modbus network (server, client, links, etc)
+
+### Expected behavior
+
+### Actual behavior
+
+### Steps to reproduce the behavior (commands or source code)
+
+### libmodbus output with debug mode enabled

libmodbus_src/MIGRATION

@@ -0,0 +1,53 @@
+=============================================
+Migration notes from the 2.0 series (for 3.0)
+=============================================
+
+The 3.0 release use a brand new API and this document covers only the general
+changes:
+
+- the structure modbus_param_t is gone and is replaced by a new opaque and
+dynamically allocated structure modbus_t.
+
+- the slave argument is no more an argument of the Modbus functions, you need to
+  call modbus_set_slave first.
+
+- the public header file is smaller so some internal defines aren't accessible
+  anymore.
+
+- all function and constants are respectively prefixed by modbus_ or MODBUS_.
+
+- the POSIX error conventions are used (if an error occured, -1 or NULL is
+  returned and errno is set accordingly).
+
+- coil status and discretes inputs are just bits and force/preset actions have
+  been renamed to write actions.
+
+We hope you'll enjoy the new API to accept the migration burden!
+
+=============================================
+Migration notes from the 1.2 series (for 2.0)
+=============================================
+
+Init
+====
+
+modbus_init_tcp requires a third new argument, the port number.
+
+modbus_init_tcp(modbus_param_t *mb_param, char *ip_address, int port)
+
+Set the port to MODBUS_TCP_DEFAULT_PORT to use the default one
+(502). It's convenient to use a port number greater than or equal to
+1024 because it's not necessary to be root to use this port number.
+
+
+Pointers of data
+================
+
+The coil and input status are now stored in an array of type uint8_t
+(in 1.2.X series, array of type int was used).  So now, you need to
+pass a pointer of type uint8_t to use read_coil_status(), for example.
+
+The holding and input registers are now stored in an array of type
+uint16_t.
+
+These changes reduce the memory consumption.

libmodbus_src/Makefile.am

@@ -0,0 +1,16 @@
+CLEANFILES =
+ACLOCAL_AMFLAGS = -I m4 ${ACLOCAL_FLAGS}
+AM_MAKEFLAGS = --no-print-directory
+
+pkgconfigdir = $(libdir)/pkgconfig
+pkgconfig_DATA = libmodbus.pc
+EXTRA_DIST = libmodbus.pc.in
+CLEANFILES += libmodbus.pc
+
+dist_doc_DATA = MIGRATION README.md
+
+SUBDIRS = src doc
+
+if BUILD_TESTS
+SUBDIRS += tests
+endif