3.4.6Link Timeout
The Purpose of the Parameter
Link timeout is the maximum time you will allow for a slave device to respond to a command issued at the BM85 Modbus slave port In your application, if the timeout value is exceeded, a `slave device down` error code will be returned by the program function initiating the command to the device
If the timeout value is too short, slower devices may not have time to respond normally to their commands, resulting in apparent errors at the device If the value is too long, and a device fails to respond, your application will have to wait until the timeout occurs before handling the device condition or using the port again
A value should be set to handle the slowest device at the port, without excessive delay The value should accommodate the sum of the following:
Vserial communication time
Vslave device processing time: for example, controller scan time
VBM85 processing time for port transactions, approximately 4 ms
Setting the Parameter
You set each port's timeout parameter as a value in the range 1 3000 The timeout value represents multiples of 100 milliseconds
For example, a parameter of 10 specifies a link timeout of 10 x 100 ms, or one second
32 Configuring the Modbus Models | 31007492 |
