Modbus Payload Server Context Building Example

#!/usr/bin/env python
'''
Pymodbus Server Payload Example
--------------------------------------------------------------------------

If you want to initialize a server context with a complicated memory
layout, you can actually use the payload builder.
'''
#---------------------------------------------------------------------------# 
# import the various server implementations
#---------------------------------------------------------------------------# 
from pymodbus.server.sync import StartTcpServer

from pymodbus.device import ModbusDeviceIdentification
from pymodbus.datastore import ModbusSequentialDataBlock
from pymodbus.datastore import ModbusSlaveContext, ModbusServerContext

#---------------------------------------------------------------------------# 
# import the payload builder
#---------------------------------------------------------------------------# 

from pymodbus.constants import Endian
from pymodbus.payload import BinaryPayloadDecoder
from pymodbus.payload import BinaryPayloadBuilder

#---------------------------------------------------------------------------# 
# configure the service logging
#---------------------------------------------------------------------------# 
import logging
logging.basicConfig()
log = logging.getLogger()
log.setLevel(logging.DEBUG)

#---------------------------------------------------------------------------# 
# build your payload
#---------------------------------------------------------------------------# 
builder = BinaryPayloadBuilder(endian=Endian.Little)
builder.add_string('abcdefgh')
builder.add_32bit_float(22.34)
builder.add_16bit_uint(0x1234)
builder.add_8bit_int(0x12)
builder.add_bits([0,1,0,1,1,0,1,0])

#---------------------------------------------------------------------------# 
# use that payload in the data store
#---------------------------------------------------------------------------# 
# Here we use the same reference block for each underlying store.
#---------------------------------------------------------------------------# 

block = ModbusSequentialDataBlock(1, builder.to_registers())
store = ModbusSlaveContext(di = block, co = block, hr = block, ir = block)
context = ModbusServerContext(slaves=store, single=True)

#---------------------------------------------------------------------------# 
# initialize the server information
#---------------------------------------------------------------------------# 
# If you don't set this or any fields, they are defaulted to empty strings.
#---------------------------------------------------------------------------# 
identity = ModbusDeviceIdentification()
identity.VendorName  = 'Pymodbus'
identity.ProductCode = 'PM'
identity.VendorUrl   = 'http://github.com/bashwork/pymodbus/'
identity.ProductName = 'Pymodbus Server'
identity.ModelName   = 'Pymodbus Server'
identity.MajorMinorRevision = '1.0'

#---------------------------------------------------------------------------# 
# run the server you want
#---------------------------------------------------------------------------# 
StartTcpServer(context, identity=identity, address=("localhost", 5020))