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What modbus function codes are supported by Modicon M238 Controller.

Refer to attached file for Modbus function codes supported by M238 Controller as modbus slave.


1.Out of %MW register access possible to read and write
for bit access only read access is available,but the bit element is an extract of %MW.
 
All M238 Controller bit %MX0.0 to MX0.7 + %MX1.0 to MX1.7 are member of the register %MW0 .
 
2.No direct access to %MB,where %MW0 include %MB0+%MB1.
 
3.For Bit access for bit access read,the rule is same for read %I function request 2 and %Q function request1.
 
4.To acces to a bit number n between 0 and 7 of mapped object byte I_QX.i.n of M238 Controller
For First byte,number is n
For second byte,number is n+8
For third byte,number is n+16
 
For byte number I,number is n+ (i)*8
 
For number 15,this is the High upper bit located in the secoond byte  is %Ix1.7.
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