Such as title, the original poster wants to send instructions 0 x12345 to from machine A and machine B, A, B in the list of connected devices on the host index 0, 1, respectively, and the host sends commands AT + TX=0, 0 x12345 AT + TX=1, 0 x12345, but my host operation AT the same time send above 2 instruction, will find that the data received from the machine A: 0 x12345 AT + TX=1, 0 x12345, is sent to all the data from the machine B is received from the machine A, this kind of situation?