Omega Engineering PCI-DAS1001, Руководство пользователя

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7.3.4 CALIBRATION REGISTER
See "Calibrating The PCI-DAS1000" document for additional programming details.
BADR1 + 6
This register controls all autocal operations. This is a Write-only register.
WRITE
- - - - - - - -
SEL8800 SEL7376 - CSRC0 CSRC1 CSRC2 CALEN SDI
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
SEL8800
This bit enables the 8-bit trim DACs for the following circuits:
ADC Fine Offset
7
ADC Coarse Offset
6
DAC1 Coarse Gain 5
DAC1 Fine Gain 4
DAC1 Offset
3
DAC0 Offset
2
DAC0 Coarse Gain 1
DAC0 Fine Gain 0
Cal Function DAC Channel
SEL7376
This bit latches the 7-bit serial data stream into the AD7376 digital potentiometer
(10KOhm). The AD7376 is used for analog front-end gain calibration.
CSRC[2:0]
These bits select the different calibration sources available to the ADC front end.
VDAC1 1 1 1
VDAC0 0 1 1
8.6mV 1 0 1
0.875V 0 0 1
1.75V 1 1 0
3.5V 0 1 0
7.0V 1 0 0
AGND 0 0 0
Cal Source CSRC0 CSRC1 CSRC2
CALEN
This bit is used to enable Cal Mode.
1 = Selected Cal Source, CSRC[2:0], is fed into Analog Channel 0.
0 = Analog Channel 0 functions as normal input.
SDI
Serial Data In. This bit is used to set serial address/data stream for the
DAC8800 TrimDac and 7376 digital potentiometer. Used in conjunction
with SEL8800 and SEL7376 bits.
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