HT45R37
PWM Programming Example
The following sample program shows how the PWM output is setup and controlled.
mov a,64h
mov pwm0h,a
clr pwm0l
clr pdc.0
set pwm0en
set pd.0
; setup PWM0 value to 1600 decimal which is 640H
; setup PWM0H register value
; setup PWM0L register value
; setup pin PD0 as an output
; set the PWM0 enable bit
; Enable the PWM0 output
:
:
:
:
clr pd.0
; PWM0 output disabled - PD0 will remain low
f
S
Y
S
[
[
[
P
P
P
W
W
W
M
M
M
]
]
]
=
=
=
1
1
1
6
6
6
0
0
0
0
1
2
P
P
P
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W
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M
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1
1
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0
0
0
0
1
1
/
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2
2
2
5
5
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6
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6
1
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2
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/
f
8+4 PWM Mode
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0
H
~
P
W
M
1
H
P
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M
0
L
~
P
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1
L
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b
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~
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1
PWM Register Pairs
Rev. 1.20
32
February 25, 2011
HOLTEK [ HOLTEK SEMICONDUCTOR INC ]
