Core Timer
16-22
ADSP-BF535 Blackfin Processor Hardware Reference
Core Timer Control Register (TCNTL)
When the timer is enabled by setting the
TMREN
bit in the
TCNTL
register,
shown in
Figure 16-14
, the
TCOUNT
register is decremented once every
TSCALE
+1 number of clock cycles. When the value of the
TCOUNT
register
reaches 0, an interrupt is generated and the
TINT
bit is set in the
TCNTL
reg-
ister. If the
TAUTORLD
bit in the
TCNTL
register is set, then the
TCOUNT
register is reloaded with the contents of the
TPERIOD
register and the count
begins again.
The core timer can be put into low power mode by clearing the
TMPWR
bit
in the
TCNTL
register. Before using the timer, set the
TMPWR
bit. This
restores clocks to the timer unit. When
TMPWR
is set, the core timer may
then be enabled by setting the
TMREN
bit in the
TCNTL
register.
Hardware behavior is undefined if
TMREN
is set when
TMPWR
= 0.
Figure 16-13. Core Timer Block Diagram
DEC
TSCALE
CCLK
TIMER ENABLE
AND PRESCALE
LOGIC
ZERO
TCOUNT
TCNTL
TPERIOD
COUNT REGISTER
LOAD LOGIC
TIMER
INTERRUPT
T
IN
T
T
M
R
E
N
CORE MMR BUS
Содержание ADSP-BF535 Blackfin
Страница 80: ...Development Tools 1 26 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 312: ...Working With Memory 6 86 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 332: ...System Interfaces 7 20 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 360: ...Dynamic Power Management Controller 8 28 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 446: ...Beginning and Ending an SPI Transfer 10 40 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 522: ...Timing Examples 11 76 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 562: ...IrDA Support 12 40 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 608: ...PCI I O Issues 13 46 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 672: ...References 14 64 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 810: ...SDRAM Controller SDC 18 86 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 811: ...ADSP BF535 Blackfin Processor Hardware Reference 18 87 External Bus Interface Unit...
Страница 812: ...SDRAM Controller SDC 18 88 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 860: ...DMA Bus Debug Registers 20 30 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 908: ...SDRAM Controller External Bus Interface Unit B 36 ADSP BF535 Blackfin Processor Hardware Reference...