GMS90C320

16

OCT. 2000 Ver 1.2

Timer 2

Timer 2 is a 16-bit Timer/Counter with an up/down count feature. It can operate either as timer or as an event counter which

is selected by bit C/T2 (T2CON.1).

It has three operating modes as shown in Table 5.

1Note:

↓ =

falling edge

Table 5

Timer/Counter 2 Operating Modes

Mode

T2CON

T2MO

D

DECN

T2CON

EXEN

P1.1

T2EX

Remarks

Input Clock

RxCLK

or

TxCLK

CP/

RL2

TR2

Internal

External

(P1.0/T2)

16-bit Auto-

reload

0

0

0

0

0

0

0

0

1

1

1

1

0

0

1

1

0

1

X

X

X

↓

0

1

reload upon overflow

reload trigger (falling edge)

Down counting

Up counting

max.

16-bit

Capture

0

0

1

1

1

1

X

X

0

1

X

↓

16-bit Timer/Counter (only

up-counting)

capture

TH1, TL2

→ RC2H, RC2L

max.

Baud Rate

Generator

1

1

X

X

1

1

X

X

0

1

X

↓

no overflow interrupt request

(TF2)

extra external interrupt

(“Timer 2”)

max.

off

X

X

0

X

X

X

Timer 2 stops

-

-

ƒ

OSC

12

----------------

ƒ

OSC

24

----------------

ƒ

OSC

12

----------------

ƒ

OSC

24

----------------

ƒ

OSC

12

----------------

ƒ

OSC

24

----------------