Data processing and handling system with channel extender in data processor to peripheral device data transfer link.

摘要

The present invention relates to a data processing and handling system comprising a data processor (120), a processor channel (107), at least one peripheral device (100), a peripheral device controller (101) and a channel extender (103, 105) for extending the distance that the peripheral device controller may be operated from the processor channel while performing data chaining in a data streaming mode through the channel extender, in which the processor channel has the ability to control data transfer by transmitting a Suppress Output signal to the peripheral device controller in response to which the peripheral device controller stops sending or requesting data. According to the invention the system is characterised in that the channel extender (103, 105) comprises (a) first means (199, 250, 251, 252) for capturing peripheral device controller generated bytes in flight and their associated data transfer tags, (b) second means (205), coupled to the first means, for storing all captured bytes and tags, when the system is in data streaming mode from the time the processor channel transmits the Suppress Output signal at least until the time the peripheral device controller stops sending or requesting data, and (c) third means (275, 276, 277), coupled to the second means, for outputting the bytes and tags stored in the second means to the processor channel under processor channel control. c