Automatic reset signal generator integrated into chipset and chipset with reset completion indication function

• US 7,055,064 B2
• Filed: 11/21/2002
• Issued: 05/30/2006
• Est. Priority Date: 02/05/2002
• Status: Active Grant

• Current Assignee: VIA Technologies Incorporated (VIA Technologies)
• Original Assignee: VIA Technologies Incorporated (VIA Technologies)
• Inventors: Lin, Scott
• Primary Examiner(s): Beausoliel, Robert
• Assistant Examiner(s): MCCARTHY, CHRISTOPHER S
• Application Number:
  US10/301,303
• Publication Number:
  US 20030149912A1
• Time in Patent Office: 1,286 Days
• Field of Search: 714/23, 714/51, 714/34, 714/55, 327/198, 713/501
• US Class Current: 714/23
• CPC Class Codes: G06F 1/24 Resetting means

Abstract

A circuit for automatically resetting a central processing unit (CPU) is provided. The circuit includes a detector and a reset signal generator. The detector is electrically connected to the CPU for receiving a specified signal from the CPU, and the detector sends out a triggering signal when the specified signal is not received for a predetermined period of time. The reset signal generator is electrically connected to the detector for generating a reset signal in response to the triggering signal. A chipset with a reset completion indication function is also provided. The chipset includes a plurality of functional circuits and a calculating and recording device.

Claims

1. A circuit for automatically resetting a central processing unit (CPU), said circuit comprising:

a detector electrically connected to said CPU for receiving a specified signal from said CPU, said detector sending out a triggering signal when said specified signal is not received for a predetermined period of time; and

a reset signal generator comprising a sample and hold circuit electrically connected to said detector for generating a reset signal to reset said CPU by modifying a waveform of said triggering signal into said reset signal.

2. The circuit according to claim 1 wherein said specific signal is an address strobe (ADS) signal.

3. The circuit according to claim 1 wherein said detector comprises:

a counter electrically connected to said CPU, periodically counting upwards in response to a clock signal and outputting a counting value, wherein said counting value is reset in response to said specified signal; and

a triggering signal generator electrically to said counter for generating said triggering signal when said counting value reaches a preset value.

4. The circuit according to claim 3 wherein said counter is a ripple counter.

5. The circuit according to claim 3 wherein said triggering signal generator comprises an AND gate, said triggering signal is generated when all inputs of said AND gate are logically high.

6. The circuit according to claim 3 wherein said clock signal is generated from a clock signal generator, and said clock generator comprises:

a first frequency divider, frequency-dividing a system clock signal into a first frequency signal;

a second frequency divider, frequency-dividing said system clock signal into a second frequency signal; and

a first multiplexer electrically connected to said first frequency divider and said second frequency divider, and selecting one of said first frequency signal and said second frequency signal to be outputted as said clock signal in response to a first select signal.

7. The circuit according to claim 6, further comprising a first register electrically connected to said first multiplexer, and storing level data of said first select signal for selecting the output of said first multiplexer.

8. The circuit according to claim 1, further comprising a second multiplexer electrically connected to said reset signal generator and a chipset, and selecting one of said reset signal and an original reset signal from said chipset to be outputted to reset said CPU in response to a second select signal.

9. The circuit according to claim 8, further comprising a second register electrically connected to said second multiplexer, and storing level data of said second select signal for selecting the output of said second multiplexer.

10. The circuit according to claim 1, further comprising:

an accumulator electrically connected to said reset signal generator for generating an accumulating value in response to the accumulative generation of said reset signal; and

a readout register electrically connected to said accumulator for storing said accumulating value available to be read out.

11. The circuit according to claim 1, further comprising a power state circuit electrically connected to said reset signal generator for providing a power state signal to said reset signal generator, and said reset signal is outputted when said power state signal is at a normal state.

12. A circuit for automatically resetting a central processing unit (CPU), said circuit;

comprising;

a detector electrically connected to said CPU, sending out a triggering signal when detecting a specified operation of said CPU has suspended for a predetermined period of time;

a reset signal generator electrically connected to said detector, and generating a reset signal in response to said triggering signal; and

a multiplexer electrically connected to said reset signal generator and a chipset, and selecting one of said reset signal and an original reset signal from said chipset to be outputted to reset said CPU in response to a select signal.

13. A chipset with a reset completion indication function, comprising:

a plurality of functional circuits, respectively performing reset operations in response to reset signals, and outputting reset completion signals after completing said reset operations; and

a calculating and recording device, calculating and recording said reset completion signals to indicate whether reset operations of said chipset are complete and which functional circuit has not been reset.

14. The chipset according to claim 13 wherein said reset completion signals are transmitted to an external device.

15. The chipset according to claim 14 wherein said calculating and recording device comprises:

an AND gate receiving said reset completion signals and performing an AND operation on said reset completion signals, and outputting a reset completion indication signal for indicating said reset completion of said chipset; and

a first register electrically connected downstream of said AND gate for storing said reset completion indication signal to be read by said external device.

16. The chipset according to claim 15 wherein said external device is an embedded controller.

17. The chipset according to claim 16 wherein said calculating and recording device comprises an n-bit register electrically connected to said plurality of functional circuits and said embedded controller for storing said reset completion signals, and providing data stored therein for said embedded controller via a bus interface.

18. The chipset according to claim 17 wherein said bus interface is selected from one of a LPC (Low Pin Count) bus and an ISA (Industry Standard Architecture) bus.

19. The chipset according to claim 16 wherein said embedded controller is embedded in a notebook.

20. The chipset according to claim 15 wherein said external device is a central processing unit (CPU).

21. The chipset according to claim 20 wherein, said calculating and recording device comprises an n-bit register electrically connected to said plurality of functional circuits and said CPU for storing said reset completion signals, and providing data stored therein for said CPU.

22. The chipset according to claim 21 wherein said data stored in said first register and said n-bit register is read out to be stored in a functional register, and then provided for said CPU via a bus interface.

23. The chipset according to claim 22 wherein said bus interface is selected from one of a PCI (Peripheral Component Interconnect) bus and an LPC (Low Pin Count) bus.