G E N m o d u l e r e g i s t e r s

Bits

Access

Mnemonic

Reset

Description

 

 

 

 

 

D28

R/W

TPRE

0

Timer prescaler

 

 

 

 

0

Disable 9-bit prescaler

 

 

 

 

1

Enable 9-bit prescaler

 

 

 

 

Determines whether the 9-bit prescaler will be

 

 

 

 

used in calculating the TIMEOUT parameter. The

 

 

 

 

prescaler allows for longer TIMEOUT values.

 

 

 

 

TPRE affects TIMEOUT only when FXTALE is used

 

 

 

 

as a time source.

 

 

 

 

 

D27

R/W

TCLK

0

Timer clock source

 

 

 

 

0

Use FXTALE as timer clock source

 

 

 

 

1

Use FSYSCLK as timer clock source

 

 

 

 

Selects the reference clock for the timer module.

 

 

 

 

 

D26:00

R/W

ITC

0

Initial timer count

 

 

 

 

Defines the TIMEOUT parameter for interrupt

frequency. The TIMEOUT period is a function of the FXTALE.

Table 27: Timer Control registers bit definition

7 2

N S 7 5 2 0 H a r d w a r e R e f e r e n c e , R e v . D 0 3 / 2 0 0 6

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Image 86
Digi NS7520 manual Timer prescaler, Timer clock source, Initial timer count