Eagle Technology PC104PLUS-26, Руководство пользователя

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PCI 730 & PC104P-30 User Manual Eagle Technology - Data Acquisition
Analog Input
The PCI730 has got 16 single ended or 8 differential analog inputs that can be configured for
a number of gain settings. Using different gain setting will give you a higher degree of
accuracy.
When in differential mode every eighth channel is configured as a pair, i.e. CH0 and CH8.
Reading a single voltage from a channel
To read a single ADC channel you need to know the voltage range and gain.
API-CALL
Long EDRE_ADSingle (ulng Sn, ulng Channel, ulng Gain, ulng Range, plong uVoltage)
Parameter Type Description
Sn Unsigned long Board’s serial number
Channel Unsigned long ADC Channel
Gain Unsigned long ADC Gain
Range Unsigned long ADC Range
uVoltage Pointer to a long Voltage read from channel
Return Long Error Code
Table 4-7 AD Single Read parameters
ACTIVEX CALL
Long EDREADX.SingleRead (long Channel)
Parameter Type Description
Channel Long ADC Channel
Return Long Voltage returned from channel.
Make sure to set the
Gain and Range properties of the ADC ActiveX control. This will in turn
set the gain and range when reading the ADC channel.
Value Input Mode
0 Single Ended
1 Differential
Table 4-8 SingleRead Range Codes
Value Gain Range
0 1.0 ±
2.5V
1 0.5 ±
5V
2 0.25 ±
10V
Table 4-9 SingleRead Gain Codes
Configuring the ADC subsystem for scanning
This is the most complicated part of configuring the PCI730 for auto scanning. Make sure that
you use the correct format when applying the channel list configuration. There are many
loopholes and care should be taken when implementing code to configure the PCI730.
API-CALL
Long EDRE_ADConfig (ulng Sn, pulng Freq, ulng ClkSrc, ulng Burst, ulng Range,
pulng ChanList, pulng GainList, ulng ListSize)
The following parameters must be specified when configuring the ADC sub-system.
Parameter Type Description
Sn Unsigned long Board’s serial number.
Freq Pointer to an
unsigned long Sampling frequency. The actual sampling frequency will be returned with this parameter.
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