Samsung C8249 Manuel D’Utilisation
S3C8245/P8245/C8249/P8249
8-BIT TIMER A/B
11-9
F
PROGRAMMING TIP — To generate 38 kHz, 1/3duty signal through P3.0
This example sets Timer B to the repeat mode, sets the oscillation frequency as the Timer B clock source, and
TBDATAH and TBDATAL to make a 38 kHz,1/3 Duty carrier frequency. The program parameters are:
TBDATAH and TBDATAL to make a 38 kHz,1/3 Duty carrier frequency. The program parameters are:
17.59
µ
s
37.9 kHz 1/3 Duty
8.795
µ
s
— Timer B is used in repeat mode
— Oscillation frequency is 4 MHz (0.25
µ
s)
— TBDATAH = 8.795
µ
s/0.25
µ
s = 35.18, TBDATAL = 17.59
µ
s/0.25
µ
s = 70.36
— Set P3.0 to TBPWM mode.
ORG
0100H
;
Reset address
START
DI
•
•
•
LD
TBDATAL,#(70-2)
;
Set 17.5
µ
s
LD
TBDATAH,#(35-2)
;
Set 8.75
µ
s
LD
TBCON,#00000110B
;
Clock Source
←
fxx
;
Disable Timer B interrupt.
;
Select repeat mode for Timer B.
; Start Timer B operation.
; Set Timer B Output flip-flop (TBOF) high.
;
; Set Timer B Output flip-flop (TBOF) high.
;
LD
P3CONL,#02H
;
Set P3.0 to TBPWM mode.
;
This command generates 38 kHz, 1/3 duty pulse signal
through P3.0.
through P3.0.
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•
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