MC912DG128ACPVE Datasheet, PDF (387/478 Pages) Freescale Semiconductor, Inc – Upward compatible with M68HC11 instruction set

Freescale Semiconductor, Inc.
Analog-to-Digital Converter
ATD Registers
Table 19-8 lists the special channels. The last column in the table
denote the expected digital code that should be generated by the
special conversion for 8-bit resolution.
CC, CB, CA — Analog Input Channel Select Code
These bits select the analog input channel(s). Table 19-9 lists the
coding used to select the various analog input channels. In the case
of single channel scans (MULT=0), this selection code specifies the
channel for conversion. In the case of multi-channel scans (MULT=1),
this selection code represents the first channel to be examined in the
conversion sequence. Subsequent channels are determined by
incrementing the channel selection code; selection codes that reach
the maximum value wrap around to the minimum value.
Note that for special conversion mode, bits CC/CB/CA have a
different function. Instead of specifying the analog input channel, they
identify which special channel conversion is to take place. (See Table
19-8.) A summart of the channels converted and the associated result
locations for multiple channel scans can be found in Table 19-10.
Table 19-9. Analog Input Channel Select Coding
CC
CB
CA
0
0
0
0
0
1
0
1
0
0
1
1
1
0
0
1
0
1
1
1
0
1
1
1
Analog Input
Channel
AD0
AD1
AD2
AD3
AD4
AD5
AD6
AD7
MC68HC912DT128A — Rev 4.0
MOTOROLA
Analog-to-Digital Converter
For More Information On This Product,
Go to: www.freescale.com
Technical Data
387