ADLINK DAQe-2502 - Manual (Page 72)

62 Appendix
Iterative Generation w. Intermediate Space
Utilize DLY2_counter to separate consecutive
waveform generations in iterative generation
mode. In this demo, the original standard sine
wave is repeated several times as specified in
IC_counter, with intermediate space deter-
mined by DLY2_counter.
Piece-wise Generation
When the value specified in UC_counter is
smaller than the sample size of waveform, the
waveform is generated piece-wisely. The inter-
mediate space between each piece is deter-
mined by DLY2_counter. In this demo, the
UC_counter is set to 1/8 of the sample size of
waveform.
Amplitude Modulated
When external D/A reference is used, applying
sinusoidal voltage reference will result in an
amplitude modulated (AM) waveform genera-
tion. You can use one D/A channel to generate
sine wave, loop it back to AOEXTREF_A/B pin,
and generate AM waveform by another D/A
channel using external reference. All can be
done in a single D/A group.
Frequency Modulated
By feeding AFI0/AFI1 with PWM source, pulse
train from VCO, or any time-varying digital signal,
DAQ-/DAQe-/PXI-2502/2501 is capable of
generating frequency modulated (FM) waveform.
Since all four channels are synchronized in a D/A
group, precise quadrature waveform generation is
guarantied, provided the waveform are shifted 90-
degree for the other channel. Phase difference of
any degree can also be setup. Combined with
external High-speed programmable Digital I/O
card, Phase-Shift-Keying or Phase-Reversal-
Keying can also be achieved.