Datasheet

Chapter 14 Analog-to-Digital Converter (S08ADC10V1)
MC9S08AW60 Data Sheet, Rev 2
240 Freescale Semiconductor
7654 3 210
R COCO
AIEN ADCO ADCH
W
Reset: 0 0 0 1 1 1 1 1
= Unimplemented or Reserved
Figure 14-3. Status and Control Register (ADC1SC1)
Table 14-3. ADC1SC1 Register Field Descriptions
Field Description
7
COCO
Conversion Complete Flag — The COCO flag is a read-only bit which is set each time a conversion is
completed when the compare function is disabled (ACFE = 0). When the compare function is enabled (ACFE =
1) the COCO flag is set upon completion of a conversion only if the compare result is true. This bit is cleared
whenever ADC1SC1 is written or whenever ADC1RL is read.
0 Conversion not completed
1 Conversion completed
6
AIEN
Interrupt Enable — AIEN is used to enable conversion complete interrupts. When COCO becomes set while
AIEN is high, an interrupt is asserted.
0 Conversion complete interrupt disabled
1 Conversion complete interrupt enabled
5
ADCO
Continuous Conversion Enable — ADCO is used to enable continuous conversions.
0 One conversion following a write to the ADC1SC1 when software triggered operation is selected, or one
conversion following assertion of ADHWT when hardware triggered operation is selected.
1 Continuous conversions initiated following a write to ADC1SC1 when software triggered operation is selected.
Continuous conversions are initiated by an ADHWT event when hardware triggered operation is selected.
4:0
ADCH
Input Channel Select — The ADCH bits form a 5-bit field which is used to select one of the input channels. The
input channels are detailed in Figure 14-4.
The successive approximation converter subsystem is turned off when the channel select bits are all set to 1.
This feature allows for explicit disabling of the ADC and isolation of the input channel from all sources.
Terminating continuous conversions this way will prevent an additional, single conversion from being performed.
It is not necessary to set the channel select bits to all 1s to place the ADC in a low-power state when continuous
conversions are not enabled because the module automatically enters a low-power state when a conversion
completes.
Figure 14-4. Input Channel Select
ADCH Input Select ADCH Input Select
00000 AD0 10000 AD16
00001 AD1 10001 AD17
00010 AD2 10010 AD18
00011 AD3 10011 AD19
00100 AD4 10100 AD20
00101 AD5 10101 AD21
00110 AD6 10110 AD22
00111 AD7 10111 AD23