Action

Sets the clock divisor.

 

 

Syntax

CONFIG CLOCKDIV = constant

 

Remarks

 

The options to set the clock divisor is available in most new chips. Under normal conditions the clock divisor is one. Thus an oscillator value of 8 MHz will result in a system clock of 8 MHz. With a clock divisor of 8, you would get a system clock of 1 MHz.

Low speeds can be used to generate an accurate system frequency and for low power consumption.

Some chips have a 8 or 16 division enabled by default by a fuse bit.

You can then reprogram the fuse bit or you can set the divisor from code.

 

When you set the clock divisor take care that you adjust the $CRYSTAL directive also.

$CRYSTAL specifies the clock frequency of the system. So with 8 MHz clock and divisor of 8 you would specify $CRYSTAL = 1000000.

 

Some older chips use a different method for clock division. These chips do not support CONFIG CLOCK but they might support CLOCKDIVSION.

 

 

See also

$CRYSTAL , CLOCKDIVISION

 

 

Example

CONFIG CLOCKDIV = 8 'we divide 8 MHz crystal clock by 8 resulting in 1 MHz speed