ADSP-BF537 Blackfin Processor Hardware Reference
20-9
Dynamic Power Management
Full On Mode
Full on mode is the maximum performance mode. In this mode, the PLL
is enabled and not bypassed. Full on mode is the normal execution state of
the processor, with the processor and all enabled peripherals running at
full speed. The system clock (
SCLK
) frequency is determined by the
SSEL
-specified ratio to
VCO
. DMA access is available to L1 and external
memories. From full on mode, the processor can transition directly to
active, sleep, or deep sleep modes, as shown in
Active Mode
In active mode, the PLL is enabled but bypassed. Because the PLL is
bypassed, the processor’s core clock (
CCLK
) and system clock (
SCLK
) run at
the input clock (
CLKIN
) frequency. DMA access is available to appropri-
ately configured L1 and external memories.
In active mode, it is possible not only to bypass, but also to disable the
PLL. If disabled, the PLL must be re-enabled before transitioning to full
on or sleep modes.
From active mode, the processor can transition directly to full on, sleep, or
deep sleep modes.
Sleep Mode
Sleep mode significantly reduces power dissipation by idling the core pro-
cessor. The
CCLK
is disabled in this mode; however,
SCLK
continues to run
at the speed configured by
MSEL
and
SSEL
bit settings. Since
CCLK
is dis-
abled, DMA access is available only to external memory in sleep mode.
From sleep mode, a wakeup event causes the processor to transition to one
of these modes:
• Active mode if the
BYPASS
bit in the
PLL_CTL
register is set
• Full on mode if the
BYPASS
bit is cleared
Summary of Contents for Blackfin ADSP-BF537
Page 42: ...Contents xlii ADSP BF537 Blackfin Processor Hardware Reference ...
Page 90: ...Development Tools 1 32 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 138: ...Programming Examples 4 26 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 340: ...SDC Programming Examples 6 84 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 606: ...Programming Examples 9 94 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 660: ...Programming Examples 10 54 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 720: ...Electrical Specifications 11 60 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 840: ...Programming Examples 13 42 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 876: ...Programming Examples 14 36 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 938: ...Programming Examples 15 62 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 958: ...Programming Examples 17 12 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 986: ...Programming Examples 18 28 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 1162: ...G 26 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 1218: ...Index I 56 ADSP BF537 Blackfin Processor Hardware Reference ...