Method and apparatus for connecting single master devices to a multimaster wired-and bus environment
US6591322B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 1, 2000 |
| Grant date | Jul 8, 2003 |
| Priority date | — |
| Expiry date | Sep 21, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F13/4031
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A “firewall” apparatus is placed between a single bus master device and a multimaster I2C bus system. The firewall apparatus transforms all multimaster bus errors into simple NAK errors and isolates the single bus master from the multimaster bus. Therefore the single bus master needs only to retry transactions that receive unexpected NAKs and all complex multimaster issues, such as bus collisions, transaction termination and bus recovery, associated with the actual error that occurred on the multimaster bus are handled by the firewall apparatus. In accordance with one embodiment, when the single bus master attempts to launch a transaction at a time when the multimaster I2C bus is busy, the firewall apparatus absorbs the address driven by the single bus master and then stalls the transaction until the firewall apparatus is able to successfully acquire and drive the address on the multimaster bus. The firewall apparatus is implemented in a preferred embodiment by a programmed microcontroller.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.