Fast-sleep configuration for CDMA slotted mode

1. A timing system for a wireless mobile station, the system comprising:

a communication element operating to communicate with a remote station; and

a circuit that enables the mobile station to enter a low-power mode after a next timing boundary when a command is received;

wherein the circuit artificially slews local system time upon receipt of said command so that the next timing boundary occurs substantially immediately.

2. The system of claim 1 , wherein said timing boundary is a pseudo-random noise sequence roll boundary, and said circuit includes a counter to receive a pseudo-random noise sequence, said counter estimating a number of clock cycles to a next pseudo-random noise sequence roll boundary.

3. The system of claim 2 , wherein said circuit further includes a wakeup time register to receive a sleep time value in terms of a number of pseudo-random noise roll boundaries, said wakeup time register providing a new sleep time value that includes said number of clock cycles to said next pseudo-random noise sequence roll boundary.

4. The system of claim 3 , wherein said wakeup time register includes a summing element that sums said received sleep time value with said number of clock cycles to said next pseudo random noise sequence roll boundary.

5. The system of claim 3 , wherein said circuit further includes a sleep timer configured to issue a sleep command at the beginning of said low-power mode, and to keep internal time during said low-power mode, said sleep timer providing a wakeup signal when said internal time reaches said new sleep time value.

6. The system of claim 5 , wherein said sleep timer includes a signal generator operating to generate said wakeup signal based on said internal time and said new sleep time value.

7. A method for managing sleep timing operations in a CDMA slotted-paging mode, comprising:

monitoring allotted slots or interrupts;

waking up at an appropriate time to service said slots or interrupts;

immediately entering a low-power mode when commanded;

slewing local system time before entering said low-power mode:

determining a difference between said slewed local system time and correct system time that corresponds to said allotted slots; and

incorporating said difference into the duration of said low-power mode.

8. The method of claim 7 , wherein said timing operations include:

storing a calculated wakeup time including time to next pseudo-random noise sequence roll boundary, upon command to enter a low-power mode; and

transitioning into said low-power mode without waiting for said roll boundary.

9. The method of claim 8 , further comprising:

receiving a wakeup time based only on a number of pseudo-random nose sequence roll boundaries;

estimating said time to next pseudo-random noise sequence roll boundary; and

providing said calculated wakeup time based on said time to next pseudo-random noise sequence roll boundary and said wakeup time based only on said number of pseudo-random noise roll boundaries.

10. The method of claim 8 , further comprising:

providing an internal sleep time; and

transitioning out of said low-power mode when said sleep time reaches said calculated wakeup time.

11. A method for managing sleep timing operations in a wireless mobile device, comprising:

slewing a local time reference so that an artificial timing roll boundary occurs immediately upon a command to enter a low-power mode, wherein said artificial timing roll boundary occurs sooner than a next timing roll boundary;

storing a calculated wakeup time based in part on a time period to said next timing roll boundary, upon the command to enter said low-power mode; and

transitioning into said low-power mode in accordance with said local time reference without waiting for said next timing roll boundary.

12. A computer program on a computer-readable storage medium having executable instructions that enable a mobile station to enter a low-power mode substantially immediately upon command, said program enabling the computer to:

slew a local time reference so that an artificial timing roll boundary occurs immediately upon a command to enter a low-power mode, wherein said artificial timing roll boundary occurs sooner than a next timing roll boundary;

store a calculated wakeup time based in part on a time period to said next timing roll boundary, upon the command to enter said low-power mode; and

transition into said low-power mode in accordance with said local time reference without waiting for said next timing roll boundary.

13. A wireless telephone device, comprising:

a housing; and

a sleep timing system within the housing, said system enabling the device to enter a low-power mode after a next roll boundary when a command is received;

wherein the sleep timing system artificially slews local system time upon receipt of said command so that the next roll boundary occurs substantially immediately.

14. The device of claim 13 , wherein said roll boundary is a pseudo-random noise sequence roll boundary.

15. The device of claim 14 , wherein said sleep timing system includes:

a counter to receive a pseudo-random noise sequence, said counter estimating a number of clock cycles to said next pseudo-random noise sequence roll boundary;

a wakeup time register to receive a sleep time value in terms of number of pseudo-random noise roll boundaries, said wakeup time register providing a new sleep time value that includes said number of clock cycles to said next pseudo-random noise sequence roll boundary; and

a sleep timer configured to issue a sleep command at the beginning of said low-power mode, and to keep internal time during said low-power mode, said sleep timer providing a wakeup signal when said internal time reaches said new sleep time value.

16. A method for managing sleep timing operations in a wireless mobile device, comprising:

computing a time difference between a first system time that corresponds to a desired start time of sleep and a second system time that corresponds to a system time event;

slewing a local reference clock from a first time that is synchronized with system timing to a second time that is offset from the system timing by the time difference; and

entering sleep when the local reference clock reaches a local time event.

17. The method of claim 16 , further comprising:

returning the local reference clock to the first time synchronized with the system timing after sleep.

18. The method of claims 16 , wherein stewing the local reference clock comprises setting the local reference clock behind to indicate thereafter a time that is earlier than actual system time.

19. The method of claim 16 , wherein stewing the local reference clock comprises setting the local reference clock ahead to indicate thereafter a time that is later than actual system time.

20. The method of claim 16 , wherein the local reference clock includes a timing counter that maintains a time count.

21. The method of claim 20 , wherein the system time event is a rollover of the time count that would occur in the future if the local system clock remained synchronized to system time, and

the local time event is a rollover of the time count of the slewed local reference clock that occurs earlier than the system time event.

22. The method of claim 16 , further comprising:

determining a third time corresponding to a desired future time to wakeup from sleep;

computing a sleep duration based on the third time; and

exiting sleep when the sleep duration has expired.

23. The method of claim 16 , wherein the sleep duration includes the time difference.

24. A timing system for a wireless mobile station that uses periodic timing boundaries to control a low-power mode, the timing system comprising:

a counter that determines a time interval to a next timing boundary upon receiving a command;

a calculating element that calculates a sleep time period based on the time interval; and

a signal generator that produces a sleep command signal after the calculating element calculates the sleep time period so that the wireless mobile station enters the low-power mode without waiting the next timing boundary, and produces a wakeup signal when the sleep time period has elapsed.

25. The timing system according to claim 24 , wherein the calculating element has a summing element that adds the time interval to a normal sleep time to calculate the sleep time period, wherein the normal sleep time is defined by the timing boundaries.

26. The timing system according to claim 24 , wherein the command is issued when user input is ended.