SN8P2711A
8-Bit Micro-Controller
SONiX TECHNOLOGY CO., LTD
Page 102
Version 0.1
8.4.4 PWM PROGRAM EXAMPLE
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Example: Setup PWM0 output from TC0 to PWM0OUT (P5.4). The external high-speed oscillator clock is
4MHz. Fcpu = Fosc/4. The duty of PWM is 30/256. The PWM frequency is about 1KHz. The PWM clock
source is from external oscillator clock. TC0 rate is Fcpu/4. The TC0RATE2~TC0RATE1 = 110. TC0C =
TC0R = 30.
MOV
A,#01100000B
B0MOV
TC0M,A
; Set the TC0 rate to Fcpu/4
MOV
A,#30
; Set the PWM duty to 30/256
B0MOV
TC0C,A
B0MOV
TC0R,A
B0BCLR
FTC0OUT
; Set duty range as 0/256~255/256.
B0BCLR
FALOAD0
B0BSET
FPWM0OUT
; Enable PWM0 output to P5.4 and disable P5.4 I/O function
B0BSET
FTC0ENB
; Enable TC0 timer
Note: The TCnR is write-only register. Don’t process them using INCMS, DECMS instructions.
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Example: Modify TC0R registers’ value.
MOV
A, #30H
; Input a number using B0MOV instruction.
B0MOV
TC0R,
A
INCMS
BUF0
; Get the new TC0R value from the BUF0 buffer defined by
NOP
;
programming.
B0MOV
A,
BUF0
B0MOV
TC0R,
A
Note: The PWM can work with interrupt request.