TIMER/COUNTER UNIT

Register Name:

Register Mnemonic:

Register Function:

15

E

I

I

 

N

N

N

 

 

H

T

 

 

 

 

 

Timer 2 Control Register

T2CON

Defines Timer 2 operation.

M

C

0

C

O

N

T

A1298-0A

Bit

Bit Name

Reset

 

 

Function

Mnemonic

State

 

 

 

 

 

 

 

 

 

 

 

 

EN

Enable

0

Set to enable the timer. This bit can be written

 

 

 

only when the

INH

bit is set.

 

 

 

 

INH

Inhibit

X

Set to enable writes to the EN bit. Clear to

 

 

 

ignore writes to the EN bit. The

INH

bit is not

 

 

 

stored; it always reads as zero.

 

 

 

 

INT

Interrupt

X

Set to generate an interrupt request when the

 

 

 

Count register equals a Maximum Count

 

 

 

register. Clear to disable interrupt requests.

 

 

 

 

MC

Maximum

X

This bit is set when the counter reaches a

 

Count

 

maximum count. The MC bit must be cleared

 

 

 

by writing to the Timer Control register. This

 

 

 

is not done automatically. If MC is clear, the

 

 

 

counter has not reached a maximum count.

 

 

 

 

CONT

Continuous

X

Set to cause the timer to run continuously.

 

Mode

 

Clear to disable the counter (clear the EN bit)

 

 

 

after each counting sequence.

 

 

 

 

 

 

 

 

NOTE: Reserved register bits are shown with gray shading. Reserved bits must be written to a logic zero to ensure compatibility with future Intel products.

Figure 9-6. Timer 2 Control Register

9-9

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Image 238
Intel 80C188XL Timer 2 Control Register, T2CON, Defines Timer 2 operation, Maximum count. The MC bit must be cleared