Data processing device with direct memory access function processed as an micro-code vectored interrupt
US5063498A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 20, 1989 |
| Grant date | Nov 5, 1991 |
| Priority date | — |
| Expiry date | Jul 20, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F13/32
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
In this data processing device, a request for direct memory-access operation is detected as an interrupt signal. When such an interrupt is detected, a interrupt controller generates a vector corresponding to the interrupt sigal. On the basis of this vector, a DMA controller generates a control signal showing whether the interrupt signal is a normal interrupt or an interrupt for requesting the direct memory-access operation. A CPU includes a ROM for storing micro-code for achieving the direct memory-access operation. When the DMA controller generates a control signal corresponding to the interrupt signal, the CPU sequentially reads out the micro-codes, to execute the direct memory-access operation. Specifically, if an interrupt for requesting the direct memory-access operation is detected, different processing space from that used for a normal interrupt processing is accessed. The processing space has a prestorage of the data corresponding to the data stored in various types of registers provided in the conventional DMA controller. By using this data, the data transfer is controlled by the micro-codes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.