Inhibiting Input Output Retries
Original Publication Date: 1981-Jul-01
Included in the Prior Art Database: 2005-Feb-11
The present disclosure is an improvement over the channel command retry (CCR) set forth in U. S. Patent 3,688,274. In a control unit having plural levels of control, a channel level can provide channel command retries to received commands. A more remote level of control, such as a microprocessor or device adapter, can inhibit the sending of a CCR by the channel level whenever an error condition has occurred, an anomaly status has been generated or because of other unique status. In particular, when a subsystem is attempting to respond to the subsequently reissued command (following the end of the full CCR sequence), then the subsystem's ability to inhibit further CCR on that command is beneficial.