User Manual

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 If the framing signal is set to CS (or ~CS), the first clock edge seen after the CS (or
~CS) signal transitions from low to high (or high to low) is the first clock in the serial
stream.
 Press the CS or ~CS softkey and turn the Universal Knob to select the channel that is
connected to the SPI frame line. The label (~CS or CS) for the source channel is
automatically set from the Cs Type softkey's setting. The data pattern and the clock
transition must occur during the time when the framing signal is valid. The framing
signal must be valid for the entire data pattern.
 If the framing signal is set to CLK Timeout, the oscilloscope generates its own internal
framing signal after it sees inactivity on the serial clock line.
 CLK Timeout: Select Clock Timeout in the Cs Type softkey. Select the Limit softkey
and turn the Universal Knob to set the minimum time that the Clock signal must be
idle (i.e., no transitions) before the oscilloscope will search for the Data pattern on
which to trigger. The Limit value can be set from 100 ns to 1 s.
b. Press the Threshold softkey and turn the Universal Knob to select the chip select signal
threshold voltage level. The threshold voltage level is used in decoding. It will become
the trigger level when the trigger type is set to the selected serial decode slot.
12. Press the Bit Order softkey to set the bit order to LSB or MSB according to the input signal.
SPI Serial Decode
To set up SPI serial decode:
1. Press the Decode button to display the DECODE menu.
Figure 113 - SPI DECODE menu
2. Press the Data Length softkey and turn the Universal Knob to set the number of bits in the
SPI decoded data.
3. Press the Display softkey and choose On to display the decode line on the display.
4. Press the List softkey to enter the LIST menu.
5. Press the Display softkey and choose Decode 1 or Decode 2 to display the decode list on the
display.
6. Press the Scroll softkey and the Lines softkey to set the position of the cursor and the number
of lines in the list with the Universal Knob. The range of the Lines setting is 1 to 7.