Agilent Technologies InfiniiVision 3000 X- Series Advanced Training Manual page 80

4
Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs
Figure 55 Capturing 4-wire SPI signals using the scope's digital channels of acquisition
You should now see four digital waveforms captured by the scope's digital
channels of acquisition similar to
being generated by the scope's built- in pattern generator and routed
directly to the scope's digital acquisition system; bypassing the logic probe.
Note that in a real measurement application such as this, you would use
the scope's analog input channels and/or logic probe to capture these
signals from your system.
D9 is the MOSI data signal (Master- out, Slave- in), and D8 is the MISO
data signal (Master- in, Slave- out). You can also think of these signals as
serial data- out and serial data- in relative to the Master. D7 is the SPI
clock signal (CLK), and D6 is the chip select low- enable signal (~CS). This
signal is sometimes referred to as Slave- select (SS). Note that the "~"
symbol simply means "not" or "low- enable". Let's now set up the scope to
decode these SPI signals.
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(MSO).
Press the [Serial] front panel key.
2
Press the Mode I C softkey; then select SPI using the Entry knob.
Press the Signals softkey.
Press the Clock softkey; then select D7 as the clock source using the
Entry knob.
Press the (Back) front panel button to return to the previous menu.
Back
Press the MOSI softkey; then select D9 using the Entry knob.
Press the (Back) front panel button to return to the previous menu.
Back
Figure 55. These SPI training signals are
3000 X-Series Oscilloscopes Advanced Training Guide