MC9S12HY64 Datasheet, PDF (295/792 Pages) Freescale Semiconductor, Inc – S12 Microcontrollers

Analog-to-Digital Converter (ADC12B8CV1) Block Description
Table 8-14. ATDCTL5 Field Descriptions (continued)
Field
4
MULT
3–0
CD, CC,
CB, CA
Description
Multi-Channel Sample Mode — When MULT is 0, the ATD sequence controller samples only from the specified
analog input channel for an entire conversion sequence. The analog channel is selected by channel selection
code (control bits CD/CC/CB/CA located in ATDCTL5). When MULT is 1, the ATD sequence controller samples
across channels. The number of channels sampled is determined by the sequence length value (S8C, S4C, S2C,
S1C). The first analog channel examined is determined by channel selection code (CD, CC, CB, CA control bits);
subsequent channels sampled in the sequence are determined by incrementing the channel selection code or
wrapping around to AN0 (channel 0).
0 Sample only one channel
1 Sample across several channels
Analog Input Channel Select Code — These bits select the analog input channel(s) whose signals are
sampled and converted to digital codes. Table 8-15 lists the coding used to select the various analog input
channels.
In the case of single channel conversions (MULT=0), this selection code specifies the channel to be examined.
In the case of multiple channel conversions (MULT=1), this selection code specifies the first channel to be
examined in the conversion sequence. Subsequent channels are determined by incrementing the channel
selection code or wrapping around to AN0 (after converting the channel defined by the Wrap Around Channel
Select Bits WRAP3-0 in ATDCTL0). In case of starting with a channel number higher than the one defined by
WRAP3-0 the first wrap around will be AN7 to AN0.
Table 8-15. Analog Input Channel Select Coding
SC
CD
CC
CB
CA
0
0
0
0
0
0
0
0
1
0
0
1
0
0
0
1
1
0
1
0
0
0
1
0
1
0
1
1
0
0
1
1
1
1
0
0
0
1
0
0
1
1
0
1
0
1
0
1
1
1
1
0
0
1
1
0
1
1
1
1
0
1
1
1
1
Analog Input
Channel
AN0
AN1
AN2
AN3
AN4
AN5
AN6
AN7
AN7
AN7
AN7
AN7
AN7
AN7
AN7
AN7
MC9S12HY/HA-Family Reference Manual, Rev. 1.04
Freescale Semiconductor
295