Agilent Technologies 2000 X-Series, Руководство пользователя

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I2C/SPI Triggering and Serial Decode
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Agilent InfiniiVision 2000 X-Series Oscilloscopes User's Guide 317
4
Press the
Trigger:
softkey; then, turn the Entry knob to select the trigger
condition:
•
Start Condition
— The oscilloscope triggers when SDA data transitions
from high to low while the SCL clock is high. For triggering purposes
(including frame triggers), a restart is treated as a start condition.
•
Stop Condition
— The oscilloscope triggers when data (SDA) transitions
from low to high while the clock (SCL) is high.
• Missing Acknowledge — The oscilloscope triggers when SDA data is high
during any Ack SCL clock bit.
•
Address with no Ack
— The oscilloscope triggers when the acknowledge
of the selected address field is false. The R/W bit is ignored.
• Restart — The oscilloscope triggers when another start condition occurs
before a stop condition.
•
EEPROM Data Read
— The trigger looks for EEPROM control byte value
1010xxx on the SDA line, followed by a Read bit and an Ack bit. It
then looks for the data value and qualifier set by the
Data softkey
and the
Data is
softkey. When this event occurs, the oscilloscope will
trigger on the clock edge for the Ack bit after the data byte. This
data byte does not need to occur directly after the control byte.
SDA
SCL
Stop
Condition
R/
Start
Condition
Ack
Ack
Data
Address
SDA
SCL
Control
byte
Read
R/
Ack
Data
Ack
Trigger point
Start or
Restart
Condition