mc68hc908lb8 Freescale Semiconductor, Inc, mc68hc908lb8 Datasheet - Page 50

• Manufacturer Part Number: mc68hc908lb8
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

Analog-to-Digital Converter (ADC)
3.8.2 ADC Data Register
One 8-bit result register is provided. This register is updated each time an ADC conversion completes.
3.8.3 ADC Clock Register
The ADC clock register (ADCLK) selects the clock frequency for the ADC.
ADIV2–ADIV0 — ADC Clock Prescaler Bits
50
ADIV2–ADIV0 form a 3-bit field which selects the divide ratio used by the ADC to generate the internal
ADC clock.
approximately 1 MHz.
NOTES:
Address:
1. If any unused channels are selected, the resulting ADC conversion will be unknown or re-
2. V
Table 3-2
Reset:
Reset:
Read:
Read:
Write:
Write:
served.
REFH
and V
NOTES:
$003E
ADIV2
AD7
Bit 7
1. X = Don’t care
0
shows the available clock configurations. The ADC clock should be set to
ADIV2
Address:
REFL
0
0
0
0
1
Figure 3-5. ADC Clock Register (ADCLK)
= Unimplemented
= Unimplemented
are internally connected to V
ADIV1
Figure 3-4. ADC Data Register (ADR)
AD6
6
0
Table 3-2. ADC Clock Divide Ratio
$003F
ADIV1
MC68HC908LB8 Data Sheet, Rev. 1
X
0
0
1
1
(1)
ADIV0
AD5
5
0
ADIV0
X
0
1
0
1
(1)
Unaffected by reset
AD4
4
0
0
DD
ADC input clock ÷ 1
ADC input clock ÷ 2
ADC input clock ÷ 4
ADC input clock ÷ 8
ADC input clock ÷ 16
and V
AD3
3
0
0
ADC Clock Rate
SS
respectively.
AD2
2
0
0
AD1
1
0
0
Freescale Semiconductor
AD0
Bit 0
0
0