GPS GPS-1000X Series, Руководство пользователя

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User Manual
79
IIC Trigger and Serial Decode
Please take the order of “ Setup for IIC Signals ”, “ IIC Triggering ” and “ IIC Decode ” to
trigger and decode the signals.
Setup for IIC Signals
IIC (Inter- IC bus) signals setup consists of connecting the oscilloscope to the serial data
(SDA) line and the serial clock (SCL) line and then specifying the input signal threshold
voltage levels.
To set up the oscilloscope to capture IIC signals, use the Signal softkey which appears in
the Decode Menu:
1. Press the Decode button on the front panel to turn on the DECODE function menu.
2. Press the Serial softkey and select the desired slot (Serial 1 or Serial 2).
3. Press the Decode option and select IIC with the Universal Knob , and then push
down the Universal Knob to confirm.
Figure 34 IIC SINGAL Menu
4. Press Signal softkey to enter the IIC SIGNAL menu.
5. 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 Universal Knob to select the
channel for the signal.
c. Press the corresponding Threshold softkey; then, turn the Universal Knob to set
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).
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