float anaInDiff(unsigned int channel, unsigned int gaincode);

Reads the state of differential analog input channels and uses the previously set calibration constants to convert it to volts.

PARAMETERS

channel is the analog input channel number (0 to 7) corresponding to LN0_IN to LN7_IN

channel

DIFF

Voltage Range

(V)

 

 

0

+AIN0 -AIN1

-22.5 to +22.5*

1

+AIN1 -AIN1

 

 

 

2

+AIN2 -AIN3

-22.5 to +22.5*

 

 

 

3

+AIN3 -AIN3

 

 

 

4

+AIN4 -AIN5

-22.5 to +22.5*

 

 

 

5

+AIN5 -AIN5

 

 

 

6

+AIN6 -AIN7

 

 

 

7

+AIN7 -AIN7

 

 

 

* Accessible on Prototyping Board.

gaincode is the gain code of 0 to 7.

Gain Code

Multiplier

Voltage Range*

(V)

 

 

0

×1

-22.5

– +22.5

 

 

 

 

1

×2

-11.25

– +11.25

 

 

 

 

2

×4

-5.6

– +5.6

 

 

 

 

3

×5

-4.5

– +4.5

 

 

 

 

4

×8

-2.8

– +2.8

 

 

 

 

5

×10

-2.25

– +2.25

 

 

 

 

6

×16

-1.41

– +1.41

 

 

 

7

×20

-1.126 – +1.126

 

 

 

 

* Applies to Prototyping Board.

RETURN VALUE

A voltage value corresponding to the voltage differential on the analog input channel. ADOVERFLOW (defined macro = -4096) if overflow or out of range.

ADTIMEOUT (defined macro = -4095) if conversion is incomplete or busy-bit timeout.

SEE ALSO

anaInCalib, anaIn, anaInmAmps, brdInit

User’s Manual

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Image 61
Digi RCM4000 user manual Float anaInDiffunsigned int channel, unsigned int gaincode