公开(公告)号：US5499242A

公开(公告)日：1996-03-12

申请号：US381183

申请日：1995-01-31

申请人： Wesley Lee ,  Jerry Grand

发明人： Wesley Lee ,  Jerry Grand

IPC分类号： H04L12/413

CPC分类号： H04L12/40013 ,  H04L12/4135

摘要： N bit-collision circuits of a collision detection circuit each include a bit-collision circuit driver connected to drive an x-th line of the common collision detection bus if the x-th line of the station's corresponding identifier signal is at a low level. The bits of the identifier signal are only provided to the bit-collision circuit drivers while an enable signal is asserted. The driver has an open-collector-type connection to the x-th line of the common collision detection bus. That is, the bit-collision circuit driver, when not driving, presents a high impedance at its output. Each bit-collision circuit further includes an XOR device for use in comparing the level of the x-th line of the collision bus with the level of the x-th bit of the station's identifier signal. A NOR device is for combining receives the comparison results from the XOR devices of the bit-collision circuits and provides a combined bit-collision result. A global collision indication line driver has an open-collector-type output interface to a global collision indication line. The global collision indication line driver is coupled to receive the local collision result signal. If the local collision result signal has a low level, the global collision indication line driver drives its output onto the global collision indication line. Otherwise, the global collision indication line driver presents a high impedance at its output.

摘要翻译： 冲突检测电路的N个位冲突电路各自包括连接到驱动公共冲突检测总线的第x行的位冲突电路驱动器，如果站的对应标识符信号的第x行处于低电平。 标识符信号的位仅在确定使能信号时提供给位冲突电路驱动器。 驱动器具有与公共碰撞检测总线的第x行的集电极开路连接。 也就是说，位冲突电路驱动器在不驱动时在其输出端呈现高阻抗。 每个比特冲突电路还包括用于将冲突总线的第X行的电平与电台的标识符信号的第x位的电平进行比较的XOR装置。 用于组合的NOR装置接收来自比特冲突电路的异或装置的比较结果，并提供组合的比特冲突结果。 全局冲突指示线驱动器具有到全局冲突指示线的集电极开路输出接口。 全局冲突指示线驱动器被耦合以接收本地冲突结果信号。 如果局部碰撞结果信号为低电平，则全局碰撞指示线驱动器将其输出驱动到全局碰撞指示线上。 否则，全局冲突指示线驱动器在其输出端呈现高阻抗。