MC68HC908QT4CPE Datasheet, PDF (47/192 Pages) Motorola, Inc – M68HC08 Microcontrollers

Analog-to-Digital Converter (ADC)
Input/Output Registers
NOTE:
The ADC subsystem is turned off when the channel select bits are all set to 1.
This feature allows for reduced power consumption for the MCU when the ADC
is not used. Reset sets all of these bits to 1.
Recovery from the disabled state requires one conversion cycle to stabilize.
Table 3-1. MUX Channel Select
CH4 CH3 CH2 CH1 CH0
0
0
0
0
0
0
0
0
0
1
0
0
0
1
0
0
0
0
1
1
0
0
1
0
0
↓
↓
↓
↓
↓
1
1
0
1
0
1
1
0
1
1
1
1
1
0
0
1
1
1
0
1
1
1
1
1
0
1
1
1
1
1
ADC
Channel
ADC0
ADC1
ADC2
ADC3
—
—
—
—
—
—
—
—
Input Select
PTA0
PTA1
PTA4
PTA5
Unused⁽¹⁾
Reserved
Unused
V_DDA(2)
V_SSA(2)
ADC power off
1. If any unused channels are selected, the resulting ADC conversion will be
unknown.
2. The voltage levels supplied from internal reference nodes, as specified in the
table, are used to verify the operation of the ADC converter both in produc-
tion test and for user applications.
3.7.2 ADC Data Register
One 8-bit result register is provided. This register is updated each time an ADC
conversion completes.
Address: $003E
Bit 7
6
5
4
3
2
1
Bit 0
Read: AD7
AD6
AD5
AD4
AD3
AD2
AD1
AD0
Write:
Reset:
= Unimplemented
Indeterminate after reset
Figure 3-5. ADC Data Register (ADR)
MC68HC908QY/QT Family — Rev. 3
MOTOROLA
Analog-to-Digital Converter (ADC)
Data Sheet
47