MC68HC08AS32 Datasheet, PDF (53/280 Pages) Motorola, Inc – M68HC08 Family of 8-bit microcontroller units (MCUs)

ADICLK — ADC Input Clock Register Bit
ADICLK selects either 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.
(See 17.6 ADC Characteristics.)
1 = Internal bus clock
0 = External clock (CGMXCLK)
1 MHz = ^fX^CL^K^or^B^us^F^req^u^en^cy
ADIV[2:0]
NOTE: During the conversion process, changing the ADC clock will result in an incorrect
conversion.
MC68HC08AS32 — Rev. 4.1
Freescale Semiconductor
Data Sheet
53