LeCroy DDA 7 Zi series, Руководство оператора

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Operator's Manual
WP700Zi-OM-E-RevA
226
data is treated as “Most Significant
Byte (MSB) First”. This is especially
important to remember when setting up
<=, <, >, >=, INRANGE and
OUTRANGE comparison.
Note: In Hexadecimal format, data
must be entered as full bytes even
though the minimum required
acceptable entry is a nibble. If less
than a full byte is entered, then a
"don’t care" X will precede the pattern
values entered.
Condition - The DATA condition can
be set many different ways. Possible
conditions are <=, <, =, >, >=, not =, in
a range, out of a range, or don’t care.
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