3. SPI Decoding
To decode SPI signal:
(1) Connect the clock line (SCLK) and the data line (SDA) of the SPI signal to
the Signal Input Channels of the oscilloscope.
(2) Adjust to the proper time base and voltage division.
(3) In trigger menu, select Bus trigger, and select bus type as SPI, set
parameters based on the characteristics of the signal, trigger the signal
correctly and obtain stable display. Refer to "SPI Trigger" on page 52.
(4) Push the Decode button on the front panel. Select bus type as SPI. set
parameters based on the characteristics of the signal. When the
parameters are set correctly, the information carried by the signal will be
displayed.
Tip: If there are repetitive menu items in both trigger menu and decoding menu,
you can set anyone of them, the other will be changed synchronously.
Note:
⚫ Use the Trigger Level knob to adjust the thresholds of bus trigger and bus
decoding.
⚫ LS First in Bit Order menu item (Least Significant Bit First) means that the
least significant bit will arrive first: hence e.g. the hexadecimal number
0x12, will arrive as the sequence 01001000 in binary representation, will
be decoded as the reversed sequence 00010010.
SPI Decoding menu list:
Set the minimum time that the clock (SCL) signal
must be idle before the oscilloscope starts to
search for the data (SDA) on which to trigger. The
range is 30 ns to 10 s.