In network 1 Set the data of the corresponding slave
In network 2 to send the telegram to the slave , the answer is stored in VB384
I now want to read the temperature of the controller according to the protocol is the value in the holding register 256 , if I put value 40256 in the block MBUS -MSG I get nothing back from the slave , if i enter value 40257 i get the the temperature value of the controller . I suspect this is because the holding register start at 0 and MBUS - MSG value 40001 interprets as registry No. 0 . Is my reasoning correct in this?
Second problem is that I do not get the temperature from VB384 but from VB385 ?
Furthermore, the value VB385 also change (eg temperature equal to 25 ° than the value in VB385 is jumping from 25 to 5) , I now put a move instruction VB385 to VB800 whenever M0.1 comes high with a positive transition . Then, the value remains constant at the measured temperature.
Does anyone have any explanation for this problem ?
Included the pdf to the modbus protocol:
http://www.yumpu.com/en/document/view/3 ... ll-devices