HP NuDAQ I-9111DG/HR A/D Channel Read Back Register, A/D Input Signal Range Control Register

Models: NuDAQ I-9111DG/HR

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3.5A/D Channel Read Back Register

The AD channel setting can be read back from this register.

Address: BASE + 6h

Attribute: read only

Data Format:

Bit

7

6

5

4

3

2

1

0

 

 

 

 

 

 

 

 

 

BASE+6h

AS3

AS2

AS1

AS0

CN3

CN2

CN1

CN0

BASE+7h

--

--

--

--

--

--

--

--

Where:

CNn: channel number

ASn: Auto scan channel number.

There are 8 bits in this register. Under non-auto scan mode, the 4 LSBs (CN0~CN3) show thechannel number setting and the 4 MSBs (AS3~AS0) is all ‘0’. Under auto-scan mode, the 4LSBs record the ending channel number. The 4 MSBs is the selected channel, and the value will increase automatically if any A/D trigger signal is inserted.

3.6A/D Input Signal Range Control Register

The A/D range register is used to adjust the analog input ranges. This register directly controls the PGA (programmable gain amplifier). When a different gain value is set, the analog input range will be changed to the its corresponding value.

Address: BASE + 8h

Attribute: write only

Data Format:

Bit

7

6

5

4

3

2

1

0

 

 

 

 

 

 

 

 

 

BASE+8h

X

X

X

X

X

G2

G1

G0

BASE+9h

X

X

X

X

X

X

X

X

The relationship between gain setting and its corresponding A/D range is listed in the table below.

G2

G1

G0

GAIN

Analog Input Range

Gain Code used in

Software Library

 

 

 

 

 

 

 

 

 

 

 

0

0

0

1

±10V

AD_B_10_V

0

0

1

2

±5V

AD_B_5_v

0

1

0

4

±2.5V

AD_B_2_5_V

0

1

1

8

±1.25V

AD_B_1_25_v

1

0

0

16

±0.625V

AD_B_0_625_V

16 Registers Format

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HP NuDAQ I-9111DG/HR manual A/D Channel Read Back Register, A/D Input Signal Range Control Register