Claims
- 1. A timer comprising:
- a first programmable downcounter adapted to provide a first predetermined timing signal after a software programmable number of clock pulses of a predetermined frequency are counted;
- a second programmable downcounter adapted to count said first predetermined timing signal to provide a second predetermined timing signal at a predetermined software programmable multiple of said first predetermined timing signal;
- one or more predetermined software programmable registers for storing said predetermined number of clock pulses at said predetermined frequency to be counted for providing said first predetermined timing signals; and
- one or more predetermined software programmable registers for storing said predetermined multiple for providing said second predetermined timing signal, said predetermined multiple being user programmable independent of said predetermined number of clock pulses stored in said programmable registers.
- 2. The timer recited in claim 1, wherein said programmable registers are write once, read many memory devices.
- 3. The timer recited in claim 1, further including means for transferring said predetermined number of clock pulses from said programmable registers to said first downcounter every time said first downcounter counts to zero.
- 4. The timer recited in claim 1, further including means for loading said predetermined number of clock pulses from said programmable registers to said first downcounter every time said programmable registers are programmed with a new value.
- 5. The timer recited in claim 1, further including means for preventing said second downcounter from counting below zero.
Parent Case Info
This application is a continuation of U.S. patent application Ser. No. 08/475,810 filed Jun. 7, 1995, now abandoned, which is a continuation of U.S. patent application Ser. No. 08/218,413 filed Mar. 25, 1994, now abandoned.
US Referenced Citations (22)
Non-Patent Literature Citations (3)
Entry |
Joseph D.Greenfield, "Practical Digital Design Using ICs", Joh Wiley & Sons, 1983, pp. 245-266. |
Alan Clements, "Microprocessor System Design", PWS-KENT Publishing Co., 1987, pp. 385-393. |
Press Release: "Zenith Data Systems introduces new class of high-performance modular notebook PCs", May 16, 1994. |
Continuations (2)
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Number |
Date |
Country |
Parent |
475810 |
Jun 1995 |
|
Parent |
218413 |
Mar 1994 |
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