Order persistent timer for controlling events at multiple processing stations

A timing apparatus at each node in a communication network using CSMA (carrier sense multiple access) protocol, said timing apparatus providing data transmission timing information to the node to prevent collisions between data transmissions from separate nodes in the communications network, said timing apparatus at each node comprising:

• a counter accumulating a count value proportional to time periods of data packet transmissions on the network;
• a selector for providing a timing reference value, said selector switching between a first timing reference value and a second timing reference value;
• said first timing reference value corresponds to a minimum size data packet transmitted on said communications network;
• said second timing reference value is a settable value based on an ordered sequence of transmission of data packets by nodes on the communication network and controls when the node initiates transmission of a data packet on said network from the node;
• and
• a comparator having a first input coupled to said timer and a second input coupled to said selector, said comparator generating an event signal to said node when said count value exceeds said timing reference value, said event signal indicating transmission of a data packet by another node when said timing reference value is the first reference value and indicating start time for data transmission by the node when said timing reference value is said second timing reference value whereby collision of data transmissions from separate nodes is prevented.

A timing apparatus at one or more stations in a communication network for timing data processing events in a system processing data between a plurality of the stations, said timing apparatus at a station comprising:

• a traffic detector detecting a data processing event occurring between stations in the system and generating an idle signal and an active signal, the idle signal indicating an idle state where no data is being processed between stations, and the active signal indicating an active state where data is being processed between stations;
• a timer timing a deferral interval during the idle state and generating an interrupt if the deferral interval times out;
• said traffic detector resetting said timer before the deferral interval times out if said traffic detector indicates a transition to an active state during the deferral interval;
• said station in response to the interrupt initiates a data processing event between the station and another station in the system whereby the data processing event initiated from the station does not collide with another data processing event between stations.