Device and method for programming critical hardware parameters
US5220673A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 1, 1991 |
| Grant date | Jun 15, 1993 |
| Priority date | — |
| Expiry date | Aug 1, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C7/1045
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A control register residing in a circuit chip stores a set of hardware parameters which exercise programmable control over circuits in the chip to allow for various critical hardware options. A plurality of chips and their control registers may be addressed and written individually by a processor through normal bus access. Each control register is permitted to be written only once, shortly after reset. A circuit, in response to a reset signal and a chip select signal, enables the individual control register for writing, and further, in response to a write strobe, latches data from the data bus into the register and soon afterwards ceases enabling the register for further writes. The various hardware options responsive to the hardware parameters include allowing for various bus interfaces, trimming the time constant of an analog RC circuit which provides internal bus timing strobes, switching internal timing strobes to external pads for output, switching external timing strobes from external pads to replace the internal strobes, and floating the outputs of all output pad drivers for junction leakage tests.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.