Secondly , when it is two - double bus framework , the utilization of data bus and length of the data waiting queue will fall quickly 第二，采用双总线结构会使得总线负载大大降低，等候消息队长也会大大降低。
Ieee standard for mans ( metropolitan area networks ) . formerly known as qpsx ( queued packet and synchronous exchange ) , now known as dqdb ( distributed queue dual bus ) . it was approved in 1990 Ieee关于城域网标准。原来的名称为qpsx （队列分组同步交换） ，现名为dqdb （分布式队列双总线） ， 1990年获得批准。
So it must be amended according to requirements of embedded system and multiprocessor system . the new system uses arm9 core and adopts a dual buses structure : a general system bus and a can - bus 在最终实现时,由于arm9核处理器不支持smp多处理器结构,因此系统采用了一种双总线结构:一条原来意义上的系统总线,一条can总线。
