HT46R46 datasheet(26/77 Pages) HOLTEK

26 / 77 page

HT46R46/C46/R47/C47/R48A/C48A/R49

Rev. 1.30

June 5, 2008

The following diagram illustrates the waveforms associ-

ated with the 6+2 mode of PWM operation. It is impor-

tant to note how the single PWM cycle is subdivided into

4 individual modulation cycles, numbered from 0~3 and

how the AC value is related to the PWM value.

PWM Output Control

On all devices, the PWM outputs are pin-shared with

pins PD0 and PD1. To operate as PWM outputs and not

as I/O pins, the correct PWM configuration options must

be selected. A

²0² must also be written to the corre-

sponding bits in the I/O port control register PDC to en-

sure that the required PWM output pin is setup as an

output. After these two initial steps have been carried

out, and of course after the required PWM value has

been written into the PWM register, writing a

²1² to the

corresponding bit in the PD output data register will en-

able the PWM data to appear on the pin. Writing a

²0² to

the corresponding bit in the PD output data register will

disable the PWM output function and force the output

low. In this way, the Port D data output register can be

used as an on/off control for the PWM function. Note

that if the configuration options have selected the PWM

function, but a

²1² has been written to its corresponding

bit in the PDC control register to configure the pin as an

input, then the pin can still function as a normal input

line, with pull-high resistor options.

PWM Programming Example

The following sample program shows how the PWM outputs are setup and controlled. Before use the corresponding

PWM output configuration options must first be selected.

mov a,64h

; setup PWM value of 100 decimal which is 64H

mov pwm,a

clr pdc.0

; setup pin PD0 as an output

set pd.0

; PD.0=1; enable the PWM output

clr pd.0

; disable the PWM output

- PD0 will remain low

f S Y S / 2

P W M

[ P W M ] = 1 0 0

[ P W M ] = 1 0 1

P W M

[ P W M ] = 1 0 2

P W M

[ P W M ] = 1 0 3

P W M

P W M c y c l e : 2 5 6 / f S Y S

2 5 / 6 4

2 6 / 6 4

2 5 / 6 4

2 6 / 6 4

2 5 / 6 4

2 6 / 6 4

2 5 / 6 4

2 6 / 6 4

M o d u l a t i o n c y c l e 0

P W M m o d u l a t i o n p e r i o d : 6 4 / f S Y S

M o d u l a t i o n c y c l e 1

M o d u l a t i o n c y c l e 2

M o d u l a t i o n c y c l e 3

M o d u l a t i o n c y c l e 0

6+2 PWM Mode

P W M , P W M 0 , P W M 1 R e g i s t e r

b 7

b 0

A C v a l u e

D C v a l u e

Pulse Width Modulation Registers

HT46R46 датащи(PDF) 26 Page - Holtek Semiconductor Inc

HT46R46 датащи(HTML) 26 Page - Holtek Semiconductor Inc

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77

датащи скачать

ссылки URL