HTG2190 datasheet(25/50 Pages) HOLTEK

25 / 50 page

HTG2190

Rev. 1.20

July 5, 2002

Label

Bits

Function

SSL3~0

3~0

LCD common used

PFD

Enable/disable PFD output

(0=disable, 1=enable)

PFDB

Enable/disable PFDB output

(0=disable, 1=enable)

PWM1

Select PFDB/PWM1 output

(0=PWM1, 1=PFDB)

PWM2

Select

PFD/PWM2

output

(0=PWM2, 1=PFD)

COMR register

TMR3C

T3f

F1/2

F1/4

F1/8

F1/16

F1/32

F1/64

F1/128

F1/256

F1 can select 4 frequencies by mask option

Auto Mask Option

System Clock near 512kHz

fSYS/16

System Clock near 1024kHz

fSYS/32

System Clock near 2048kHz

fSYS/64

System Clock near 4096kHz

fSYS/128

Time base frequency = T3f / (256

- TMR3)

TMR3C Bit 4 to enable/disable timer counting (0=dis-

able; 1=enable)

TMR3C Bit6, always write

²1²

TMR3C Bit7, always write

²0²

TMR3C Bit 3, always write

²0²

Timer 3 has the same structure and operating manner

with timer 2, except for clock source and PFD function.

The timer 3 can be used as a time base to generate a

regular internal interrupt. The clock source of timer 3

can come from RTC OSC (X'tal 32kHz) or system clock

divided by an 8-stage prescaler. If the RTC mask option

is enabled, a 32kHz crystal is needed to connect across

XIN and XOUT pins. The 32kHz signal is processed by

an 8-stage prescaler to generate various counting clock

for timer 3. There are two registers related to timer 3;

TMR3 (24H) and TMR3C (25H). Writing data to B2, B1,

B0 (bit 2, 1, 0 of TMR3C) can generate various counting

clock.

S y s t e m C l o c k

8 - s t a g e

P r e s c a l e r

T i m e r 2

P r e l o a d R e g i s t e r

T i m e r 2

D a t a B u s

R e l o a d

O v e r f l o w

T O N

2 . H . 4

T o i n t e r r u p t

T 2 f

¸ 2

2 . H . 5

P W M 2

2 . H . 7

P W M D A C 2

P W M 1

2 . H . 6

P W M D A C 1

Timer 2

T i m e r 3

T O N

I N T

P r e l o a d

8 S t a g e P r e s c a l e r

L C D D r i v e r

( 1 0 2 4 H z )

3 2 K X ' A T L

2 E H . 7

8 S t a g e P r e s c a l e r

S y s t e m

C l o c k

. 0

. 1

T 3 f

n e a r 3 2 7 6 8 H z

¸ 3 2

m a s k o p t i o n

* I f t h e 8 C O M B / W m o d e i s s e l e c t e d , t h e v a l u e o f t h e d i v i d e r i s 6 4 .

I f t h e 1 6 C O M B / W m o d e i s s e l e c t e d , t h e v a l u e o f t h e d i v i d e r i s 3 2 .

I f t h e 8 C O M E C B m o d e i s s e l e c t e d , t h e v a l u e o f t h e d i v i d e r i s 2 .

I f t h e 1 6 C O M E C B m o d e i s s e l e c t e d , t h e v a l u e o f t h e d i v i d e r i s 1 .

Timer 3

HTG2190 Datasheet(PDF) 25 Page - Holtek Semiconductor Inc

HTG2190 Datasheet(HTML) 25 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

Datasheet Download

Link URL