ADSP-214xx SHARC Processor Hardware Reference 7-11
Pulse Width Modulation
where subscript 1 refers to the value of that register during the first half
cycle and subscript 2 refers to the value during the second half cycle. The
corresponding duty cycles are:
Figure 7-3. Center-Aligned Paired PWM in Double Update Mode,
Low Polarity
T
AH
PWMPERIOD
1
2
-----------------------------------------
PWMPERIOD
2
2
-----------------------------------------
PWMCHA
1
PWMCHA
2
PWMDT
1
PWMDT
2
––+++
t
PCLK
×=
......................
.....
......................
.....
PWMTM
1
PWMTM
2
PWMCHA
1
PWMCHA
2
PWMTM
1
2
+
0
PWMTM
1
2
PWMTM
2
2
+
0
2xPWMDT
1
2xPWMDT
2
count
pwm_ah
pwm_al
PWMTM
2
2
PWM INTERRUPT
LATCH BIT
PWM PHASE BIT
d
AL
T
AL
T
S
-----------
1
2
---
PWMCHA
1
PWMCHA
2
PWMDT
1
PWMDT
2
+++()
PWMPERIOD
1
PWMPERIOD
2
+()
-------------------------------------------------------------------------------------------------------------------------------------------
–==