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Write
Bit #
7
BASE+5
BASE+4
CL4 ~ CL0 Start Scan Channel Number
CH4 ~ CH0 Stop Scan Channel Number
BASE+4 bit 4 to bit 0, CL4 ~ CL0, act as a pointer when you program
the A/D channel setting (see previous section). When you set the
MUX start channel to an analog input channel, AIn ( n = 0, 1, 2, 3,...,
31), the gain code, B/U and S/D written to the register of BASE+2, is
for channel n.
Caution!
We recommend you set the same start and stop
channel when writing to the register BASE+2.
Otherwise, if the A/D trigger source is on, the
multiplexer will continuously scan between channels
and the range setting may be set to an unexpected
channel. Make sure the A/D trigger source is turned
off to avoid this kind of error.
The write-only registers of BASE +4 and BASE+5 control how the
multiplexers (MUXs) scan. BASE+4 bit 4 to bit 0, CL4 ~ CL0, hold
the start scan channel number, and BASE+5 bit 4 to bit 0, CH4 ~ CH0,
hold the stop scan channel number. Writing to these two registers
automatically initializes the scan range of the MUXs. Each A/D
conversion trigger also sets the MUXs to the next channel. With
continuous triggering, the MUXs will scan from the start channel to
the stop channel and then repeat. The following examples show the
scan sequences of the MUXs (all channels are set as single-ended).
MUX Control
6
5
4
CH4
CL4
Chapter 4 Register Structure and Format
3
2
1
CH3
CH2
CH1
CL3
CL2
CL1
0
CH0
CL0
25
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