GMS81C2020 Datasheet, PDF (59/92 Pages) Hynix Semiconductor – CMOS Single-Chip 8-Bit Microcontroller with A/D Converter & VFD Driver

Hyundai Micro Electronics
GMS81C2020/GMS81C2120
fXI
T1
PWM
POL=1
PWM
POL=0
00 01 02
03
04
05
7F
80
81
Duty Cycle [ 80H x 250nS = 32uS ]
3FF 00 01 02
03
Period Cycle [ 3FFH x 250nS = 255.75uS, 3.9KHz ]
T1CK[1:0] = 00 ( fXI )
PWM1HR = 0CH
T1PPR = FFH
T1PDR = 80H
Period PWM1HR3PWM1HR2
1
1
Duty PWM1HR1PWM1HR0
0
0
T1PPR (8-bit)
FFH
T1PDR (8-bit)
80H
Figure 15-11 Example of PWM at 4MHz
T1CK[1:0] = 10 ( 1uS )
PWM1HR = 00H
T1PPR = 0EH
T1PDR = 05H
Write T1PPR to 0AH
Period changed
Source
clock
T1
01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 01 02 03 04 05 06 07 08 09 0A 01 02 03 04 05
PWM
POL=1
Duty Cycle
[ 05H x 2uS = 10uS ]
Period Cycle [ 0EH x 2uS = 28uS, 35.5KHz ]
Duty Cycle
[ 05H x 2uS = 10uS ]
Duty Cycle
[ 05H x 2uS = 10uS ]
Period Cycle [ 0AH x 2uS = 20uS, 50KHz ]
Figure 15-12 Example of Changing the Period in Absolute Duty Cycle (@4MHz)
Nov. 1999 Ver 0.0
preliminary
59