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
Summary of Contents for ADSP-BF535 Blackfin
Page 80: ...Development Tools 1 26 ADSP BF535 Blackfin Processor Hardware Reference...
Page 312: ...Working With Memory 6 86 ADSP BF535 Blackfin Processor Hardware Reference...
Page 332: ...System Interfaces 7 20 ADSP BF535 Blackfin Processor Hardware Reference...
Page 360: ...Dynamic Power Management Controller 8 28 ADSP BF535 Blackfin Processor Hardware Reference...
Page 446: ...Beginning and Ending an SPI Transfer 10 40 ADSP BF535 Blackfin Processor Hardware Reference...
Page 522: ...Timing Examples 11 76 ADSP BF535 Blackfin Processor Hardware Reference...
Page 562: ...IrDA Support 12 40 ADSP BF535 Blackfin Processor Hardware Reference...
Page 608: ...PCI I O Issues 13 46 ADSP BF535 Blackfin Processor Hardware Reference...
Page 672: ...References 14 64 ADSP BF535 Blackfin Processor Hardware Reference...
Page 810: ...SDRAM Controller SDC 18 86 ADSP BF535 Blackfin Processor Hardware Reference...
Page 811: ...ADSP BF535 Blackfin Processor Hardware Reference 18 87 External Bus Interface Unit...
Page 812: ...SDRAM Controller SDC 18 88 ADSP BF535 Blackfin Processor Hardware Reference...
Page 860: ...DMA Bus Debug Registers 20 30 ADSP BF535 Blackfin Processor Hardware Reference...