hello dear forum,

I am trying to MODBUS TCP comunicate STM32 with Mach3

I have read the TCP documents in internet and learned
that first of all Mach3 send a TCP SYN message to the STM32

this time I send a SYN-ACK message to Mach3

after this Mach3 must send a ACK message to STM32 - ( according TCP documents )

as you can see in the attached picture



the SYN from Mach3 and SYN-ACK from STM32 is there
(192.168.1.2) PC (192.168.1.110) STM32

however ACK from Mach3 is missing and Mach3 reports "conection timeout"

there is a warning from Wireshark yellow coloured

what does this warning say ? what shall I do next ?

thank you

hello all ,

I have new question

can I ethernet connect Mach3 MODBUS TCP - PC to STM32 via modem router or
is it possible only with crossover cable ?

thank you