MC68HC908GR8 Datasheet, PDF (61/286 Pages) Freescale Semiconductor, Inc – M68HC08 Microcontrollers

I/O Registers
ADICLK — ADC Input Clock Select Bit
ADICLK selects either the bus clock or CGMXCLK as the input clock source to generate the internal
ADC clock. Reset selects CGMXCLK as the ADC clock source.
If the external clock (CGMXCLK) is equal to or greater than 1 MHz, CGMXCLK can be used as the
clock source for the ADC. If CGMXCLK is less than 1 MHz, use the PLL-generated bus clock as the
clock source. As long as the internal ADC clock is at approximately 1 MHz, correct operation can be
guaranteed.
1 = Internal bus clock
0 = External clock (CGMXCLK)
fxclk or bus frequency
ADIV2–ADIV0
=
1
MHz
NOTE
During the conversion process, changing the ADC clock will result in an
incorrect conversion.
MC68HC908GR8 • MC68HC908GR4 Data Sheet, Rev. 7
Freescale Semiconductor
61