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Figure 50 RS485 Anti-collision Idle Time
RS485 bus collision time: represents the waiting milliseconds the serial device server
send the second instruction after receiving the reply of the first instruction. This
parameter actually defines the speed of instruction rotation. This value is recommended
above 20ms. The "Wait max. of 3 (s)" is not required to be modified in general.
When user use ZLVircom to select the transfer protocol to
“Modbus TCP to RTU”,
ZLVircom will automatic select the above two options (unless the user manually enter the
advanced setting to remove), as well the above two time will be configured well
automatically according to baud rate. But if the user Modbus command is longer or if the
conversion protocol is "None", then the two parameters need to be manually configured.
The recommended values for configuring the above parameters are described below:
1) Figure 50 shows the "RS485 Bus Anti-collision Time", which can be set to double the
"Packet Interval" in the lower right corner of the parameter setting interface, but the
minimum cannot be less than 20.
2) As shown in figure 49 "Maximum wait time of RS485 query command", generally
determined according to the instruction length of responses back and forth, if send
instructions for N bytes, response to M byte, it is recommended that the set value is:
"packet interval" x (N + M + 5) + 100.
8. Register Package and Heartbeat Packet
Register package and heartbeat packet are a feature suitable for communication between
devices and cloud software.
8.1 Register Packet
Register package is defined as, when the computer software and the serial device server