User`s guide

Operation Theorem  39
4.1.6 A/D Data Format
The A/D data read either from A/D data port or the FIFO port is in the two‘s
complement format. As the A/D gain is 1, the A/D signal range is roughly
+10V ~ -10V bipolar. In ACL-8316, 16 bits A/D data is available. The
relationship between the voltage and the value is shown in the following table:
A/D Data (Hex) Decimal Value Voltage (Volts)
7FFF +32767 +10.00000
4000 +16384 +5.00015
0001 1 +0.00031
0000 0 0.00000
FFFF -1 -0.00031
C000 -16384 -5.00015
8001 -32767 -10.00000
8000 -32768 -10.00031
Note:
The decimal value of the A/D data is in the same sign with the bi-
polar voltage. Therefore, the sign extension conversion is not
necessary.
The A/D data format of 12 bits ACL-8312 is compatible with the 16 bits ACL-
8316. Only the 4 LSB of the 16 bits A/D data are truncated to zero. Therefore
the software is compatible for the two cards. The relationship between the
voltage and the value is shown in the following table:
A/D Data (Hex) Decimal Value Voltage (Volts)
7FF 0 +32752 +10.0000
400 0 +16384 +5.0024
001 0 +16 +0.0049
000 0 0 0.0000
FFF 0 -16 -0.0049
C00 0 -16384 -5.0024
801 0 -32752 -10.0000
800 0 -32768 -10.0049
The formula between the A/D data and the analog value is
Voltage AD data
Kgain
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110