With the RS232 serial port, the different kinds masterslavesystem of AC converters can communicate with PC under the USS protocol.
多类型变频器通过RS2 32串行口通讯，在USS通讯协议下，就可以与工控机联网。
2
So for example, it could be that the MDM system is the master and the transactional systems are the slave systems.
例如，MDM系统是主系统，而事务性系统是从系统。
3
For availability, this computing system was a redundant design, with two sets of processors and buses and the ability to switch between a master and a slave if the master was found to be unresponsive.