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limits when LM as Modbus TCP slave
#1
Thanks a lot for the LM resident script like Modbus TCP slave! We can use 125 registers at a time, right? what can i do if i need to read / write more registers? what are the limitations in this?
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#2
125 registers is ModBus standard limit. But it only applies to a single request. If you want to read/write more then send several requests.
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#3
(25.11.2020, 10:22)admin Wrote: 125 registers is ModBus standard limit. But it only applies to a single request. If you want to read/write more then send several requests.
thanks! but what about addressing with multiple requests? will the address of the first register in the second request be 0 again? oh, understand Smile addressing continues
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#4
Each read request has a starting address and a number of coils/registers to read. The starting address is an absolute value and it does not matter which address was used in previous request.
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#5
so no limits? 65536 registers can be polled?
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#6
Yes, the whole range can be used.
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#7
thank you!
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