Token Rotation Timer implementation

Token rotation timers have been shown to be an effective means for offering preferential treatment, in terms of message delays, for certain critical messages in linear (star) high-speed data bus configurations. If a token rotation timer has expired, indicating that a prescribed time has transpired during the current token rotation, then a low priority message will not be sent. If all messages are not sent on the first available token, then some degradation in overall message delay performance occurs. Several methods of token rotation timer implementation are examined to determine the relative impact of each on overall bus performance.