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C/C++ Library for DOS
5.9 _8111_AD_Set_Gain
@ Description
This function is used to set the A/D analog input range by means of writing
data to the A/D range control register. The initial value of gain is “1’ which
is set by the ACL-8111 harware. The relationship between gain and input
voltage ranges is specified by following tables:
The initial value of gain is '1‘ and input type is bipolar, which are pre-set by
the ACL-8111 hardware. The relationship between analog input voltage
range, gain and input mode are specified by following tables:
Input Range (V)
Gain
Gain Code
±
5 V
X 1
AD_GAIN_1
±
2.5 V
X 2
AD_GAIN_2
±
1.25 V
X 4
AD_GAIN_4
±
0.625 V
X 8
AD_GAIN_8
±
0.3125V
X 16
AD_GAIN_16
@ Syntax
int _8111_AD_Set_Gain( int ad_range )
@ Argument:
ad_range: the programmable range of A/D conversion,
please refer to above tabbs for the
possible values .
@ Return Code:
ERR_NoError
ERR_BoardNoInit
ERR_AD_InvalidRange
@ Example:
#include “aclerr.h”
#include “8111.h”
main()
{
_8111_Initial( CARD_1, 0x220 );
/* Assume NoError when Initialize ACL-8111
*/
_8111_AD_Set_Gain( AD_GAIN_8 );
printf( "The A/D analog input range is +/-
0.625V now.\n" );
}