
ADSP-214xx SHARC Processor Hardware Reference
7-13
Pulse Width Modulation
therefore be programmed in increments of 2
×
PCLK
(or 10 ns for a 200
MHz peripheral clock). The
PWMDTx
registers are 10-bit registers, and the
maximum value they can contain is 0x3FF (= 1023) which corresponds to
a maximum programmed dead time of:
This equates to an
PCLK
rate of 200 MHz. Note that dead time can be pro-
grammed to zero by writing 0 to the
PWMDTx
registers (see
Modulation Registers” on page A-67
).
Output Control Unit
The
PWMSEG
register contains four bits (0 to 3) that can be used to individ-
ually enable or disable each of the 4 PWM outputs.
Output Enable
If the associated bit of the
PWMSEG
register is set (=1), then the correspond-
ing PWM output is disabled, regardless of the value of the corresponding
duty cycle register. This PWM output signal remains disabled as long as
the corresponding enable/disable bit of the
PWMSEGx
register is set. In sin-
gle update mode, changes to this register only become effective at the start
of each PWM cycle. In double update mode, the
PWMSEG
register can also
be updated at the mid-point of the PWM cycle.
After reset, all four enable bits of the
PWMSEG
register are cleared so
that all PWM outputs are enabled by default.
Output Polarity
The polarity of the generated PWM signals is programmed using the
PWMPOLARITY3–0
registers, so that either active high or active low PWM
patterns can be produced. The polarity values can be changed on the fly if
Td max
,
1023
2
×
t
PCLK
×
1023
2
×
10
10
9
–
×
×
10.2
μ
s
=
=
=
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Summary of Contents for SHARC ADSP-214 Series
Page 60: ...Contents lx ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 72: ...Notation Conventions lxxii ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 130: ...Programming Model 2 52 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 264: ...Programming Models 3 134 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 290: ...Programming Model 4 26 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 296: ...Programming Model 5 6 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 396: ...Effect Latency 7 28 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 520: ...Programming Model 10 62 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 616: ...Debug Features 14 22 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 656: ...Programming Model 15 40 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 714: ...Programming Model 19 10 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 1132: ...Register Listing A 306 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 1192: ...Index I 34 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...