User`s guide

AT-S39 Command Line Interface Users Guide
107
Maximum age time
Port priority
Force version of STP or normal RSTP
Examples
The following command returns all RSTP parameter settings to their
default values:
set rstp default
The following command sets the bridge priority to 20480 (increment 5),
the hello time to 5 seconds, and the forwarding delay to 20 seconds:
set rstp priority=5 hellotime=5 forwarddelay=20
set rstp default
The following command uses the FORCEVERSION parameter to
configure the bridge to use the RSTP parameters but to transmit only
STP BPDU packets:
set rstp forceversion=forcestpcompatible