Data processing method, and data processor and printer using data processing method
US6144460A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 30, 1997 |
| Grant date | Nov 7, 2000 |
| Priority date | — |
| Expiry date | Oct 30, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F13/28
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A data processing method which efficiently performs data transfer by using a data bus with an appropriate access width corresponding to transfer data and a printer using the data processing method. In the printer, a CPU bus 70 having a 16-bit physical bus width, is shared by a CPU 21 and a DMAC 80. In a case where the CPU 21 accesses a memory via the CPU bus 70 with an 8-bit width, while the DMAC 80 accesses the memory via the CPU bus 70 with a 16-bit width, each time the DMAC 80 needs to access the memory, the DMAC 80 issues a DMA request signal to the CPU 21, requiring an exclusive access right for the CPU bus 70. In accordance with the request signal, the CPU 21 delivers the exclusive access right for the CPU bus 70 to the DMAC 80. Then the DMAC 80 controls memory access with the 16-bit width.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.