Chain manager for use in executing a chain of I/O command blocks
US5768621A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 15, 1996 |
| Grant date | Jun 16, 1998 |
| Priority date | — |
| Expiry date | Mar 15, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F13/126
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An I/O command block chain structure allows simultaneity of execution, provides a mechanism to inhibit and enable execution of an individual I/O command block, and a mechanism for establishing precedence in the sequence of execution of the I/O command blocks. After the chain is configured and stored in a memory, an I/O command in an I/O command block in the chain is executed first. Upon completion of execution of the I/O command, a chain manager is executed. The chain manager examines the chain control field in an I/O command block pointed to by a next block pointer in the I/O command block, and decides what to do with the next I/O command block based on the state of its chain control byte. The chain manager may post completion of the chain, or may simply decrement the progress count in a following I/O command block on the chain path, and return to an idle loop. Alternatively, the chain manager may decrement the progress count in a following I/O command block on the chain path, enable the following I/O command block for execution, and return to an idle loop.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.