GMS81C5108 Datasheet, PDF (58/102 Pages) Hynix Semiconductor – HYNIX SEMICONDUCTOR INC. 8-BIT SINGLE-CHIP MICROCONTROLLERS

GMS81C5108
fxin
T1
00
01
02
03
04
7F
80
81
3FF 00
01
02
PWM
POL=1
PWM
POL=0
Duty Cycle [80_H+1 x 250nS = 32.25uS]
Period Cycle [3FF_H x 250nS = 256uS, 3.9kHz]
T1CK[1:0] = 00 (250nS)
PWMHR = 0C_H
T1PPR = FF_H
T1PDR = 80_H
Period PWM03 PWM02
1
1
T1PPR (8-bit)
FF_H
Duty
PWM01 PWM00
0
0
T1PDR (8-bit)
80_H
Figure 12-12 Example of PWM at 4MHz
T1CK[1:0] = 10 (2uS)
PWMHR = 00_H
T1PPR = 0D_H
T1PDR = 04_H
Source
clock
Write T1PPR to 09_H
Period changed
T1
00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 00 01 02 03 04 05 06 07 08 09 00 01 02 03 04
PWM
POL=1
Duty Cycle
[04_H+1 x 2uS = 10uS]
Duty Cycle
[04_H+1 x 2uS = 10uS]
Duty Cycle
[04_H+1 x 2uS = 10uS]
Period Cycle [0D_H+1 x 2uS = 28uS, 35.7kHz]
Period Cycle [09_H+1 x 2uS = 20uS, 50kHz]
Figure 12-13 Example of Changing the Period in Absolute Duty Cycle (@4MHz)
Example:
Timer1 @4Mhz, 4kHz - 20% duty PWM mode
LDM R3DR,#0000_XX1XB ;R31 output
LDM TM1,#0010_0000B ;pwm enable
LDM T1PWHR,#0000_1100B ;20% duty
LDM T1PPR,#1110_0111B ;period 250uS
LDM T1PDR,#1100_0111B ;duty 50uS
LDM RSR,#X1XX_XXXXB ;set pwm port.
LDM TM1,#0010_0011B ;timer1 start
X means don’t care
JUNE 2001 Ver 1.0
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