Omega Engineering OMB-1108-0901 用户手册
1-8 Overview & Theory of Operation
09-06-02
DaqTemp User’s Manual
Analog Input Channels
The DaqTemp Series PCI Boards allow analog input configuration for the voltage input channels and the
thermocouple input channels.
thermocouple input channels.
Channel Selection and Mode Settings
The DaqTemp module accepts up to 7 differential inputs.
The DaqTemp module accepts up to 7 differential inputs.
Channel Range and Polarity
Each of the seven differential voltage input channels may be programmed for either unipolar or bipolar
mode with gain settings of 1, 2, 4, 8, 16, 32 or 64.
Each of the seven differential voltage input channels may be programmed for either unipolar or bipolar
mode with gain settings of 1, 2, 4, 8, 16, 32 or 64.
Digital Input Channels
The DaqTemp Series PCI Boards allow either synchronous scanning of digital input channels or
asynchronous I/O operations for all configured digital channels.
asynchronous I/O operations for all configured digital channels.
Counter Input Channels
The DaqTemp Series PCI Boards allow synchronous scanning of the 4 16-bit counter input channels. The
four 16-bit counter channels can also be cascaded into two 32-bit counter channels. For either cascaded or
non-cascaded counter channels each channel can be configured for:
four 16-bit counter channels can also be cascaded into two 32-bit counter channels. For either cascaded or
non-cascaded counter channels each channel can be configured for:
• Pulse Counting Mode – specifies that each counter should be cleared upon being read and placed into
the input scan.
• Totalize Counting Mode – specifies that each counter is to free-run and not be cleared during the input
acquisition.
Synchronous Input Acquisition Clocking
The DaqTemp Series PCI boards allow clocking of the synchronized inputs either by an internal,
programmable pacer clock or by external clocking. These products use a sequencer to implement a
multiplexing approach to gathering the input data. This means that with either internal or external clocking
the entire channel scan (including the sampling time for each channel) may not exceed the maximum
aggregate rate of 200kHz.
programmable pacer clock or by external clocking. These products use a sequencer to implement a
multiplexing approach to gathering the input data. This means that with either internal or external clocking
the entire channel scan (including the sampling time for each channel) may not exceed the maximum
aggregate rate of 200kHz.
External clocking for acquisition is accomplished by applying a TTL clock input to the A/ICLK on the
Digital and Analog IO board. With external clocking, the DaqTemp PCI board will start a scan every
time there is a rising edge on the A/ICLK input. All channels [analog and digital] within the scan group are
still measured at the 5 us/channel [or 10 µs/channel] rate, the scan stored in the sequencer will be repeated
at the rate of the A/ICLK input.
Digital and Analog IO board. With external clocking, the DaqTemp PCI board will start a scan every
time there is a rising edge on the A/ICLK input. All channels [analog and digital] within the scan group are
still measured at the 5 us/channel [or 10 µs/channel] rate, the scan stored in the sequencer will be repeated
at the rate of the A/ICLK input.
Synchronous Output Operations
The DaqTemp7A and DaqTemp14A PCI Boards allow synchronous output of any 2 or 4 DACS,
respectively. All D/A channels available may have output streamed to them and clocked out synchronously.
respectively. All D/A channels available may have output streamed to them and clocked out synchronously.
DAC output channels can be updated at the rate of an internal DAC pacer clock that is fully programmable
and separate from the acquisition pacer clock.
and separate from the acquisition pacer clock.
External clocking for analog output is also available by applying a TTL clock input to the A/OCLK on the
Digital and Analog IO board. With external clocking, the DaqTemp PCI board will update the DAC(s)
every time there is a rising edge on the A/OCLK input. All DAC channels that are enabled will be updated
at the same time. Alternatively, the DACs can be updated at the acquisition rate (either internally or
externally via A/ICLK) so that an entire scan is measured every time a DAC update is done.
Digital and Analog IO board. With external clocking, the DaqTemp PCI board will update the DAC(s)
every time there is a rising edge on the A/OCLK input. All DAC channels that are enabled will be updated
at the same time. Alternatively, the DACs can be updated at the acquisition rate (either internally or
externally via A/ICLK) so that an entire scan is measured every time a DAC update is done.