GMS84512 Datasheet, PDF (61/123 Pages) Hynix Semiconductor – 8-BIT SINGLE CHIP MICROCOMPUTER

GMS 84512 / 84524
3.6.4 PWM8H, PWM8L REGISTER
PWM register (PWM8H, PWM8L) are the data register to define 14bit PWM pulse width and it is
enable R/W. They are not fixed at reset state.
PWM8H , PWM8L DATA REGISTER
PWM8H
<00E2_H>
PWM8L
<00E3_H>
R/W
7
R/W
6
R/W
5
R/W
4
R/W
3
R/W
2
R/W
1
R/W
0
PWM8 PWM8 PWM8 PWM8 PWM8 PWM8 PWM8 PWM8
H7 H6 H5 H4 H3 H2 H1 H0
Initial Value (At Reset)
[ Undefined ]
Storage of 14-bit PWM upper 8-bit data
When PWM8L is written it is loaded in upper 8-bit of
14-bit comparator, so the width of basic pulse are
determined. When PWM8L is read, the
contents(PWM8L) of comparator is read.
¡ª
¡ª R/W R/W R/W R/W R/W R/W
7
6
5
4
3
2
1
0
¡ª
¡ª
PWM8 PWM8 PWM8 PWM8 PWM8 PWM8
L5 L4 L3 L2 L1 L0
Initial Value (At Reset)
[ Undefined ]
The number and position for added-pulse of 64
basic pulse are determined
3.6.5 The control of 14-bit PWM
¨ç Write upper data to PWM8H (definition of basic pulse width)
¨è Write lower 6-bit data to PWM8L
¨é When data are written PWM8L, the 14-bit data of PWM8 is written to compare register so,
even if you will change the upper 8-bit of output data, you will write 6bit data to PWM8L again.
But when you will change the lower 6-bit of output data, you need not write the upper 8-bit to
PWM8H again..
¨ê Output polarity is determined by POL1.( bit2 of PWM control register 2)
Default is positive polarity.(POL1=0)
¨ë PWM8 port is selected by setting EN8(bit1 of PWM ontrol register1) to “1”,
so the wave of PWM is to be output.
¨ì If CNTB(bit6 of PWMCR1) is "0", Counter is operating, on the contrary if it is "1" count stops.
This have an effect on both of them.(14-bit PWM/7-bit PWM counter)
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