User Manual

SIGLENT
78 User Manual
I2C Trigger and Serial Decode
Please in order of “Setup for I2C Signals”, “I2C Triggering” and “I2C Decode” to
trigger and decode the signals.
Setup for I2C Signals
Setting the I2C (Inter-IC bus) signal includes two steps: connecting the serial data
signal (SDA) and serial clock signal (SCK) to oscilloscope, specifying the threshold
voltage of each input signal.
1. Press Decode key to enter the DECODE function menu as Figure 34 shows.
Figure 34 I2C SINGAL Menu
2. Press the Decode softkey and select the desired slot (Decode1 or Decode2).
3. Press Protocol softkey and then select I2C by turning Universal Knob.
4. Press Signal softkey to enter the SIGNAL menu as Figure 35 shows.
Figure 35 I2C SINGAL Menu
5. Set SCL (I2C’s clock signal):
a. Press SCL softkey to select the channel that is connected to the I2C clock signal.
b. Press first Threshold softkey to set the I2C clock signal’s threshold voltage level
by Universal Knob. The threshold voltage level is for decoding, and it will be
regard as the trigger voltage level when set the trigger type to serial.
6. Set SDA (I2C’s data signal):
a. Press SDA to select the channel that is connected to the I2C data signal.
b. Press second Threshold softkey to set the I2C data signal’s threshold voltage
level by Universal Knob. The threshold voltage level is for decoding, and it will be