A2C-SG2-M12
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9.1.1
Command: Setup ADC
The global minimum, maximum and mean values are continuously updated. They can be set to the current value i.e. reset by
sending the following message:
Command
Sub Command
Data[0]
Data[1]
Data[2]
Data[3]
Data[4]
Data[5]
0x40
Channels
Polarity
Gain
Data Rate
Filter MSB
Data Rate
Filter LSB
Chop
Enabled
Buffer
Enabled
DLC = 0x08
Channels:
0x01 = Use only channel 1
0x02 = Use only channel 2
0x03 = Use both channel 1 & 2
Polarity:
0x00 = Bipolar inputs (default for strain gauge bridges)
0x01 = Unipolar inputs
Gain:
0x01 = Analogue amplifier gain = 1
0x08 = Analogue amplifier gain = 8
0x10 = Analogue amplifier gain = 16
0x20 = Analogue amplifier gain = 32
0x40 = Analogue amplifier gain = 64
0x80 = Analogue amplifier gain = 128 (recommended for strain gauge bridges)
Data Rate Filter:
Determines the digital filter and thereby the data rate of the A2C-SG. The lower the value the higher the data rate
and consequently higher noise. When chopping is disabled, a data rate value of 1 in single channel mode will give an output rate of
4700 samples per second. In dual channel mode this falls to 437 samples per second for each channel. A value of 10 results in 533
and 52 samples per second respectfully.
0x0001 - 0x03FF.
Chop Enabled:
chopping is a way to almost eliminate offset voltage errors on the expense of lower data rate. It also improves the
RMS noise, as part of the chopping is done by averaging. For a single channel measurement and a data rate value of 96, the sample
frequency becomes 12.5Hz, compared to 50Hz without chopping enabled.
0x00 = chopping disabled
0x01 = chopping enabled
Buffer Enabled:
If enabled, the input channel feeds into a high impedance input stage of the buffer amplifier. Therefore, the input
can tolerate significant source impedances and is tailored for direct connection to external resistive-type sensors such as strain
gauges or resistance temperature detectors (RTDs).
0x00 = buffer disabled
0x01 = buffer enabled
