ADSP-BF537 Blackfin Processor Hardware Reference
15-47
General-Purpose Timers
Usage of the
TIMERx_PERIOD
TIMERx_WIDTH
mode of the timer:
• In pulse width modulation mode (
PWM_OUT
), both the timer period
and timer pulse width register values can be updated “on-the-fly”
since the timer period and timer pulse width (duty cycle) register
values change simultaneously.
• In pulse width and period capture mode (
WDTH_CAP
), the timer
period and timer pulse width buffer values are captured at the
appropriate time. The timer period and timer pulse width registers
are then updated simultaneously from their respective buffers. Both
registers are read-only in this mode.
• In external event capture mode (
EXT_CLK
), the timer period register
is writable and can be updated “on-the-fly.” The timer pulse width
register is not used.
If new values are not written to the timer period register or the timer pulse
width register, the value from the previous period is reused. Writes to the
32-bit timer period register and timer pulse width register are atomic; it is
not possible for the high word to be written without the low word also
being written.
Values written to the timer period registers or timer pulse width registers
are always stored in the buffer registers. Reads from the timer period or
timer pulse width registers always return the current, active value of
period or pulse width. Written values are not read back until they become
active. When the timer is enabled, they do not become active until after
the timer period and timer pulse width registers are updated from their
respective buffers at the end of the current period. See
When the timer is disabled, writes to the buffer registers are immediately
copied through to the timer period or timer pulse width register so that
they will be ready for use in the first timer period. For example, to change
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 ...