Technical data

88 4000 X-Series Oscilloscopes Advanced Training Guide
4 Serial Bus Decoding & Triggering, Search & Navigation, and Segmented Acquisition Labs
You should now see four digital waveforms captured by the scope’s digital
channels of acquisition similar to Figure 55. These SPI training signals are
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.
12 Press the [Serial] front panel key.
13 Tap the Mode I
2
C softkey; then double- tap SPI to enable.
14 Tap the Signals softkey.
Figure 55 Capturing 4-wire SPI signals using the scope’s digital channels of acquisition
(MSO).