Patent ID: 6157967
Filing Date: 2000-12-05
Classification: G06F

Abstract:
In a processing system comprising at least a pair of transmitting/receiving elements coupled to one another by a bi-directional link for communicating multi-bit words, including multi-bit data words and multi-bit command words, a method of data communication flow control that includes the steps of:providing each of the pair of transmitting/receiving elements with a transmit clock signal that defines clock periods and is sent on the bi-directional link to the other of the pair transmitting/receiving elements;a one of the pair of transmitting/receiving elements communicating data in the form of a series of multi-bit data words to the other of the pair of transmitting/receiving devices, each of the multi-bit data words being communicated with a clock period;in absence of communicating data, the one of the pair of transmitting/receiving elements transmitting with each clock period first multi-bit command words to the other of the pair of transmitting/receiving elements; andthe one of the transmitting/receiving elements periodically sending a BUSY command word to indicate to the other of the pair of transmitting/receiving elements to at least temporarily halt communicating data or, if no data is being communicated, to not communicate data until a READY command word is sent by the one of the transmitting/receiving elements;wherein after receiving the BUSY command word, failure to receive the READY command word or a subsequent BUSY command word within a predetermined period of time by the other of the pair of transmitting/receiving elements is an error.