Advantech MIC-3716, Руководство пользователя

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C.6 MUX Control — BASE+4 and BASE+5
Table C-5: Register for multiplexer control
Write Multiplexer Control
Bit # 7 6 5 4 3 2 1 0
BASE + 5 STO3 STO2 STO1 STO0
BASE + 4 STA3 STA2 STA1 STA0
STA3 ~ STA0 Start Scan Channel Number
STO3 ~ STO0 Stop Scan Channel Number
n
When you set the gain code of analog input channel n, you
should set the Multiplexer start & stop channel number to
channel n to prevent any unexpected errors. In fact BASE+4 bit
3 to bit 0, STA3 ~ STA0, act as a pointer to channel n’s address
in the SRAM when you program the A/D channel setting (refer
to Section C. 5).
Caution!
We recommend you to 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 (Multiplexer) scan.