Merge branch '#24' into develop

README.rst

@@ -12,15 +12,15 @@ uModbus
 
 uModbus or (μModbus) is a pure Python implementation of the Modbus protocol as
 described in the `MODBUS Application Protocol Specification V1.1b3`_. uModbus
-implements both a Modbus client (or master in Modbus language) and a Modbus
-server (or slave). The "u" or "μ" in the name comes from the the SI prefix
+implements both a Modbus client (both TCP and RTU) and a Modbus TCP server
+(only TCP). ThereThe "u" or "μ" in the name comes from the the SI prefix
 "micro-". uModbus is very small and lightweight. The source can be found on
 GitHub_. Documentation is available at `Read the Docs`_.
 
 Quickstart
 ----------
 
-Creating a Modbus server is easy:
+Creating a Modbus TCP server is easy:
 
 ..
     Because GitHub doesn't support the include directive the source of
@@ -124,14 +124,14 @@ uModbus is far from complete. The next, unordered list shows what is going
 to be implemented in the future:
 
 * Support for all Modbus functions
-* Modbus RTU
+* Modbus RTU server
 * Use asyncio for handling of requests
 * Other Modbus 'flavours', so uModbus is able to handle 32 bit values.
 
 License
 -------
 
-uModbus software is licensed under `Mozilla Public License`_. © 2015 `Advanced
+uModbus software is licensed under `Mozilla Public License`_. © 2016 `Advanced
 Climate Systems`_.
 
 .. External References:

docs/source/client/index.rst

@@ -1,5 +1,5 @@
-Client
-======
+Modbus Client
+=============
 
 uModbus contains a client for Modbus TCP and Modbus RTU.
 

docs/source/client/rtu.rst

@@ -17,6 +17,9 @@ Example
     * 15: Write Multiple Coils
     * 16: Write Multiple Registers
 
+.. include:: ../../../scripts/examples/simple_rtu_client.py
+    :code: python
+
 API
 ===
 

docs/source/client/tcp.rst

@@ -10,7 +10,6 @@ this:
 .. include:: ../../../scripts/examples/simple_tcp_client.py
     :code: python
 
-
 API
 ===
 

docs/source/decompose_requests.rst

@@ -21,3 +21,10 @@ ADU for TCP/IP requests and responses
 
 .. _MODBUS Messaging on TCP/IP Implementation Guide V1.0b: http://modbus.org/docs/Modbus_Messaging_Implementation_Guide_V1_0b.pdf
 .. _MODBUS Application Protocol Specification V1.1b3: http://modbus.org/docs/Modbus_Application_Protocol_V1_1b3.pdf
+
+ADU for RTU requests and responses
+==================================
+
+.. automodule:: umodbus.client.serial.rtu
+
+.. _MODBUS over Serial Line Specification and Implementation Guide V1.02: http://www.modbus.org/docs/Modbus_over_serial_line_V1_02.pdf

docs/source/functions.rst

@@ -1,7 +1,7 @@
-Functions
----------
+Modbus Functions
+----------------
 
-The Modbus functions have been implemented.
+These Modbus functions have been implemented.
 
 01: Read Coils
 ==============

docs/source/modbus_server.rst

@@ -1,4 +1,4 @@
-Modbus server
+Modbus Server
 -------------
 
 Viewpoint

scripts/examples/simple_rtu_client.py

@@ -0,0 +1,33 @@
+#!/usr/bin/env python
+# scripts/example/simple_rtu_client.py
+import fcntl
+import struct
+from serial import Serial, PARITY_NONE
+
+from umodbus.client.serial impor rtu
+
+
+def get_serial_port():
+    """ Return serial.Serial instance, ready to use for RS485."""
+    port = Serial(port='/dev/ttyS1', baudrate=9600, parity=PARITY_NONE,
+                  stopbits=1, bytesize=8, timeout=1)
+
+    fh = port.fileno()
+
+    # A struct with configuration for serial port.
+    serial_rs485 = struct.pack('hhhhhhhh', 1, 0, 0, 0, 0, 0, 0, 0)
+    fcntl.ioctl(fh, 0x542F, serial_rs485)
+
+    return port
+
+serial_port = get_serial_port()
+
+# Returns a message or Application Data Unit (ADU) specific for doing
+# Modbus RTU.
+message = rtu.write_multiple_coils(slave_id=1, address=1, values=[1, 0, 1, 1])
+
+# Response depends on Modbus function code. This particular returns the
+# amount of coils written, in this case it is.
+response = rtu.send_message(message, serial_port)
+
+serial_port.close()

scripts/examples/simple_tcp_client.py

@@ -1,5 +1,5 @@
 #!/usr/bin/env python
-# scripts/examples/simple_client.py
+# scripts/examples/simple_tcp_client.py
 import socket
 
 from umodbus import conf

umodbus/client/serial/rtu.py

@@ -1,3 +1,25 @@
+"""
+.. note:: This section is based on `MODBUS over Serial Line Specification and
+    Implementation Guide V1.02`_.
+
+The ADU for Modbus RTU messages differs from Modbus TCP/IP messages. Messages
+send over RTU don't have a MBAP header, instead they have an Address field.
+This field contains the slave id.  A CRC is appended to the message. Below all
+parts of a Modbus RTU message are listed together with their byte size:
+
++---------------+-----------------+
+| **Component** | **Size** (bytes)|
++---------------+-----------------+
+| Address field | 1               |
++---------------+-----------------+
+| PDU           | N               |
++---------------+-----------------+
+| CRC           | 2               |
++---------------+-----------------+
+
+The CRC is calculated from the Address field and the PDU.
+"""
+
 import struct
 from serial import SerialTimeoutException
 

umodbus/client/tcp.py

@@ -3,7 +3,7 @@
 .. note:: This section is based on `MODBUS Messaging on TCP/IP
     Implementation Guide V1.0b`_.
 
-The Application Data Unit (ADU) for Modbus responses carried over a TCP/IP are
+The Application Data Unit (ADU) for Modbus messages carried over a TCP/IP are
 build out of two components: a MBAP header and a PDU. The Modbus Application
 Header (MBAP) is what makes Modbus TCP/IP requests and responsen different from
 their counterparts send over a serial line.  Below the components of the Modbus