ADSP-BF537 Blackfin Processor Hardware Reference
15-7
General-Purpose Timers
software using W1C operations to clear the interrupt request. The global
TIMER_STATUS
is 32-bits wide. A single atomic 32-bit read can report the
status of all eight timers consistently.
Before a timer can be enabled, its mode of operation is programmed in the
individual timer-specific
TIMERx_CONFIG
registers. Then, the timers are
started by writing a 1 to the representative bits in the global
TIMER_ENABLE
register.
The timer enable (
TIMER_ENABLE
) register can be used to enable all eight
timers simultaneously. The register contains eight “write-1-to-set” control
bits, one for each timer. Correspondingly, the timer disable
(
TIMER_DISABLE
) register contains eight “write-1-to-clear” control bits to
allow simultaneous or independent disabling of the eight timers. Either
the timer enable or the timer disable register can be read back to check the
enable status of the timers. A 1 indicates that the corresponding timer is
enabled. The timer starts counting three
SCLK
cycles after the
TIMENx
bit is
set.
While the PWM mode is used to generate PWM patterns, the capture
mode (
WDTH_CAP
) is designed to “receive” PWM signals. A PWM pattern is
represented by a pulse width and a signal period. This is described by the
TIMERx_WIDTH
and
TIMERx_PERIOD
register pair. In capture mode these reg-
isters are read only. Hardware always captures both values. Regardless of
whether in PWM or capture mode, shadow buffers always ensure consis-
tency between the
TIMERx_WIDTH
and
TIMERx_PERIOD
values. In PWM
mode, hardware performs a plausibility check by the time the timer is
enabled. In this case the error type is reported by the
TIMERx_CONFIG
regis-
ter and signalled by the
TOVF_ERRx
bit.
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 ...