BK Precision 2560B Series, Руководство пользователя

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Serial Trigger and Decode
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Note:
10.1.2 I2C Trigger
The I2C trigger has nine trigger conditions: ( Start, Stop, Restart, No Ack, EEPROM, 7 Addr&Data, 10 Addr&Data
and Data Length )
• Start Condition : The oscilloscope will be triggered when the SDA signal transitions from high to low while the SCL
clock is high. If it is chosen as the condition of trigger (including frame triggers), a restart will be treated as a “Start
condition”.
• Stop Condition : The oscilloscope will be triggered when SDA transitions from low to high while the SCL is high.
Figure 10.4 Start and Stop Conditions
• Restart : The oscilloscope will be triggered when another “Start condition” occurs before a “Stop condition”.
• No Ack : The oscilloscope will be triggered when SDA data is high during any SCL’s ACK bit.
• EEPROM : The trigger searches for EEPROM control byte (the value is 1010xxx) on the SDA bus where there is a
Read bit and an ACK bit behind EEPROM.
– Use the Limit Range to set the qualifier.
– Use the Data1 to set the data’s value.
If EEPROM’s data is greater than Data1, the oscilloscope will be triggered at the edge of ACK
bit behind Data byte. It’s unnecessary that the Data byte musts follow the EEPROM.
Figure 10.5 Trigger Point
• 7 address & Data : The oscilloscope will be triggered when the following conditions are satisfied:
– The address’s length must be 7 bits and the address’s value must be the same as the set value.
– Data1’s or Data2’s value is set to the same value of the signal’s data.
– Both Data1’s and Data2’s values are set and the signal has two consecutive data values, the first is value is
Data1 and the second data value is Data2.