LabJack U12, Руководство пользователя, Страница: 27 / 36

4.7 BitsToVolts
Converts a 12-bit (0-4095) binary value into a LabJack voltage.
Volts=((2*Bits*Vmax/4096)-Vmax)/Gain where Vmax=10 for SE, 20 for Diff.
Declaration:
long __cdecl BitsToVolts (
long chnum,
long chgain,
long bits,
float *volts )
Parameter Description:
Returns:
LabJack errorcodes or 0 for no error.
Inputs:
• chnum – Channel index. 0-7=SE, 8-11=Diff.
•
chgain – Gain index. 0=1, 1=2, …, 7=20.
•
bits – Binary value from 0-4095.
Outputs:
•
*volts – Voltage.
4.8 VoltsToBits
Converts a voltage to it's 12-bit (0-4095) binary representation.
Bits=(4096*((Volts*Gain)+Vmax))/(2*Vmax) where Vmax=10 for SE, 20 for Diff.
Declaration:
long __cdecl VoltsToBits (
long chnum,
long chgain,
float volts,
long *bits )
Parameter Description:
Returns:
LabJack errorcodes or 0 for no error.
Inputs:
•
chnum – Channel index. 0-7=SE, 8-11=Diff.
•
chgain – Gain index. 0=1, 1=2, …, 7=20.
• volts – Voltage.
Outputs:
• *bits – Binary value from 0-4095.
4.9 Counter
Controls and reads the counter. The counter is disabled if the watchdog timer is enabled.
Execution time for this function is 20 milliseconds or less.
Declaration:
long __cdecl Counter (
long *idnum,
long demo,
long *stateD,
long *stateIO,
long resetCounter,
unsigned long *count )