First-in/first-out data storage system
US3992699A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 13, 1974 |
| Grant date | Nov 16, 1976 |
| Priority date | — |
| Expiry date | Nov 13, 1994 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F5/085
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A first-in/first-out memory device has a shift register with a storage capacity of n stages in which data units can be stored, and a modulo-n address counter having one state representing each stage of the shift register. In one embodiment designed for fast data storage, a data unit is transferred to the input of the shift register, during a write mode, and the state of the address counter is advanced for each data unit so transferred; during a read mode, data units are recirculated from the output of the shift register to its input, the shift register is shifted n times, the state of the address counter is advanced n - 1 times, and the data unit appearing at the output of the shift register when the address counter state represents an empty shift register is retrieved. In another embodiment designed for fast data retrieval, a data unit is retrieved from the output of the shift register during a read mode and the state of the address counter is advanced for each data unit so transferred; during a write mode, data units are recirculated from the output of the shift register to its input, the shift register is shifted n times, the state of the address counter is advanced n - 1 times,…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.