DSP1611/17/18/27/28/29 DIGITAL SIGNAL PROCESSOR
Information Manual
Software Architecture
April 1998
3-58
DRAFT COPY
Lucent Technologies Inc.
3.6 Power Management
(continued)
3.6.6 Power Management Examples
The following examples illustrate the more significant options for reducing the power dissipation.
Standard Sleep Mode. This is the standard sleep mode. The alf register's AWAIT bit is set while the processor is
clocked with a high-speed clock (CKI). Peripheral units can be turned off to further reduce the sleep power.
powerc=0x00F0
/*
Turn off all peripheral units, core running with CKI*/
sleep:a0=0x8000
/*
Preload a0 with alf setting
*/
do 1 {
/*
Use cache to make instructions noninterruptible */
alf=a0
/*
Stop internal DSP clock. Interrupt circuits active*/
nop
/*
Needed for bedtime execution
*/
}
nop
/*
Only sleep power consumed here until
*/
/*
interrupt wakes up the device
*/
next: . . .
/*
User code executes here
*/
powerc=0x0
/*
Turn peripheral units back on
*/
Sleep with Slow Internal Clock
1
. In this case, the ring oscillator is selected to clock the processor before the
device is put to sleep. This will reduce the power dissipation while waiting for an interrupt to continue program
execution.
powerc=0x40F0
/*
Turn off all peripheral units and select slow clock*/
2*nop
/*
Wait for it to take effect
*/
sleep:a0=0x8000
/*
Preload a0 with alf setting
*/
do 1 {
/*
Use cache to make instructions noninterruptible */
alf=a0
/*
Stop internal DSP clock. Interrupt circuits active*/
nop
/*
Needed for bed-time execution
*/
}
nop
/*
Only sleep power consumed here until
*/
/*
interrupt wakes up the device
*/
next: . . .
/*
User code executes here
*/
powerc=0x00F0
/*
Select high-speed clock
*/
2*nop
/*
Wait for it to take effect
*/
powerc=0x0000
/*
Turn peripheral units back on
*/
1.In this case, the wake-up latency is determined by the period of the ring oscillator clock.
Содержание DSP1611
Страница 18: ...Chapter 1 Introduction...
Страница 27: ...Chapter 2 Hardware Architecture...
Страница 52: ...Chapter 3 Software Architecture...
Страница 116: ...Chapter 4 Instruction Set...
Страница 154: ...Chapter 5 Core Architecture...
Страница 176: ...Chapter 6 External Memory Interface...
Страница 208: ...Chapter 7 Serial I O...
Страница 237: ...Chapter 8 Parallel I O DSP1617 Only...
Страница 261: ...Chapter 9 Parallel Host Interface PHIF DSP1611 18 27 28 29 Only...
Страница 275: ...Chapter 10 Bit I O Unit...
Страница 284: ...Chapter 11 JTAG Test Access Port...
Страница 306: ...Chapter 12 Timer...
Страница 313: ...Chapter 13 Bit Manipulation Unit...
Страница 325: ...Chapter 14 Error Correction Coprocessor DSP1618 28 Only...
Страница 350: ...Chapter 15 Interface Guide...
Страница 367: ...Appendix A Instruction Encoding...
Страница 379: ...Appendix B Instruction Set Summary...
Страница 381: ...aD extractz aS IM16 B 52 aD insert aS arM B 53 aD insert aS IM16 B 54 aD aS aaT B 55...
Страница 437: ...Index...