LeCroy DDA 7 Zi series, Руководство оператора

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Operator's Manual
WP700Zi-OM-E-RevA
220
Oftentimes, I
2
C utilizes DATA bytes to specify sub-addresses for accessing memory locations in EEPROMs.
Conditional DATA trigger allows triggering on a range of DATA bytes that correspond to reads or writes to
specific sub-address memory blocks in the EEPROM. It can also aid in monitoring DATA outputs from I
2
C-
based sensors, such as analog-to-digital converters, and triggering when DATA is outside a safe operating
range. In both cases, verifying proper operation becomes a simple task.
Pattern Length - The pattern length value defaults to the length, in bytes, of the pattern set in the Pattern Value
selection. If you were to change the length to be less than this value, it would truncate the beginning of the
pattern value. If you were to increase the pattern length, it would add "don’t care" XX byte values to the
beginning of the pattern value.
Start Byte - This selection is present only when the Trigger Selection is EEPROM or ADDR+DATA with an
INRANGE or OUTRANGE Data Condition. For EEPROM, use this to specify a particular location of data, such
as a sub-address memory block, that the Pattern Value must occupy in order for triggering to occur. For
ADDR+DATA, use this to specify a location where the data values should be placed without using don’t care (X)
values in the pattern value (X values would be nonsensical in an INRANGE or OUTRANGE conditional setup).
Values can be set from 0-2047 bytes. Setting to -1 creates a "Don’t Care" condition for data value location.
Note: The first byte is counted as Byte 0, not Byte 1.
Note: Setting the Start Byte to -1 will result in a Don’t Care setting for Start Byte. Trigger will occur no matter
where the data is in the data string. This is a good trigger debugging tool if your trigger is failing to work as you
expect.
Frame Length Setup
This setup selection is displayed if the Trigger Selection is FRAME LENGTH. It is used to trigger on a specific
Address value with a defined length of data bytes.
Bytes Length - Specify a data length
value between 0 and 2047. The
default value is 1.
If the Data Length Condition (see
below ) is selected to be either
INRANGE or OUT(of)RANGE, then
this selection will be for the minimum
data length value (i.e., the lower value
of the range you wish to include or
exclude).