Commit 5f77c11403e585fb09b30c13264a82aa229bded0

Authored by Stéphane Raimbault
1 parent 7fe4a917

Updated libmodbus.txt documentation

Showing 1 changed file with 27 additions and 4 deletions
doc/libmodbus.txt
... ... @@ -54,9 +54,13 @@ Modbus RTU message must be transmitted continuously without inter-character
54 54 hesitations (extract from Wikipedia, Modbus, http://en.wikipedia.org/wiki/Modbus
55 55 (as of Mar. 13, 2011, 20:51 GMT).
56 56  
  57 +The Modbus RTU framing calls a slave, a device/service which handle Modbus
  58 +requests, and a master, a client which send requests. The communication is
  59 +always initiated by the master.
  60 +
57 61 Many Modbus devices can be connected together on the same physical link so you
58 62 need to define which slave is concerned by the message with
59   -linkmb:modbus_set_slave[3]. If you're running a slave (server) the slave number
  63 +linkmb:modbus_set_slave[3]. If you're running a slave, the slave number
60 64 is used to filter messages.
61 65  
62 66 Create a Modbus RTU context::
... ... @@ -124,10 +128,11 @@ Flush a connection::
124 128 linkmb:modbus_flush[3]
125 129  
126 130  
127   -Data
128   -~~~~
  131 +Client
  132 +~~~~~~
129 133 The Modbus protocol defines different data types and functions to read and write
130   -them from/to remote devices.
  134 +them from/to remote devices. The following functions are used by the clients to send
  135 +Modbus requests:
131 136  
132 137 Read data::
133 138 linkmb:modbus_read_bits[3]
... ... @@ -141,6 +146,24 @@ Write data::
141 146 linkmb:modbus_write_bits[3]
142 147 linkmb:modbus_write_registers[3]
143 148  
  149 +Raw requests::
  150 + linkmb:modbus_send_raw_request[3]
  151 + linkmb:modbus_receive_confirmation[3]
  152 +
  153 +
  154 +Server
  155 +~~~~~~
  156 +The server is waiting for request from clients and must answer when it is
  157 +concerned by the request. The libmodbus offers the following functions to
  158 +receive and reply:
  159 +
  160 +Receive::
  161 + linkmb:modbus_receive[3]
  162 + linkmb:modbus_receive_from[3]
  163 +
  164 +Reply::
  165 + linkmb:modbus_reply[3]
  166 +
144 167  
145 168 ERROR HANDLING
146 169 --------------
... ...