362 Agilent InfiniiVision 3000 X-Series Oscilloscopes User's Guide
24 I2C/SPI Triggering and Serial Decode
 
4 Press the Mode softkey; then, select I2C trigger type.
5 Press the Signals softkey to open the I
2
C Signals Menu.
6 For both the SCL (serial clock) and SDA (serial data) signals:
a Connect an oscilloscope channel to the signal in the device under 
test.
b Press the SCL or SDA softkey; then, turn the Entry knob to select the 
channel for the signal.
c Press the corresponding Threshold softkey; then, turn the Entry knob 
to select the signal threshold voltage level.
The threshold voltage level is used in decoding, and it will become 
the trigger level when the trigger type is set to the selected serial 
decode slot.
Data must be stable during the whole high clock cycle or it will be 
interpreted as a start or stop condition (data transitioning while the 
clock is high).
The SCL and SDA labels for the source channels are automatically set.
I2C Triggering
To set up the oscilloscope to capture I2C signals, see "Setup for I2C 
Signals" on page 361.
After the oscilloscope has been set up to capture I2C signals, you can 
trigger on a stop/start condition, a restart, a missing acknowledge, an 
EEPROM data read, or on a read/write frame with a specific device 
address and data value.
1 Press  [Trigger]; then, select the I2C trigger type.
2 Press  [Trigger].