Micro-controller unit for selectively accessing an internal memory or an external extended memory using a read/write terminal
Abstract
Abstract A micro-controller unit (MCU) selectively accesses one of an external extended memory and an internal memory in response to a signal on a read/write terminal instead of an additional terminal. The micro-controller unit includes an external memory control block, an external timing control block, and the internal memory, and additionally includes a reset detection circuit, a memory access clock generation circuit and a latch. The reset detection circuit receives an external reset signal for initializing the MCU and an external clock, and detects whether the micro-controller unit is reset. The memory access clock generation circuit receives an output signal from the reset detection circuit and generates a memory access clock signal to selectively access one of the internal memory and the external extended memory. The latch receives the external reset signal, the memory access clock signal and a memory interface signal applied to the read/write terminal for applying a memory access selection signal to the external memory control block, the external timing control block and the internal memory, whereby a memory selection is performed by the reset signal and the memory interface signal.
Inventors
- 👤 Byeongjun Lee
Bibliographic Details
Claims Analysis
Total Claims: 6References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-12-05 | 1998-06-06 | 1998-12-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-12-05 | 2002-06-06 | 2002-12-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-12-05 | 2006-06-06 | 2006-12-06 | $7700.00 | Window Closed / Lapsed |