LeCroy DDA 7 Zi series, Operator'S Manual

Page: 224 / 544

WavePro 7Zi
223
WP700Zi-OM-E-RevA
SPI Decode Setup Detail
The SPI Decode Setup Right-Hand Dialog (which is part of the Decode Setup when SPI is selected as the
Protocol to decode), with detail on the setup conditions, is shown in the images that follow:
Viewing - Select to view the protocol data in either Binary, Hexadecimal, or ASCII
modes.
Note: The trigger setup can be different than the decode setup.
Level Type and Level - The message decoding algorithm setup is performed here.
The level is normally set up in %, and defaults to 50%. To adjust the level, touch
inside the number area to highlight the box title in yellow, then use the oscilloscope
front panel
A
DJUST
knob to adjust. Or touch inside the number area twice and select a
value using the pop-up numeric keypad.
The set Level appears as a dotted horizontal line across the oscilloscope grid.
If your initial decoding indicates that there are a number of error frames, make sure
that the level is set to a reasonable value.
Include R/W Bit - Some engineers think of the 7-bit address pattern as including the
R/W bit (i.e., 8 bits) and others think of the address pattern as not including the R/W
bit (i.e., 7 bits). If you decoded I
2
C messages include 7-bit addresses, Touch the
checkbox if you want to include the R/W bit in the decoded Address value.
Note: There is an identical checkbox selection in the I
2
C trigger setup dialog.
These two setups are dynamically linked, so selecting it one way for Decode will
result in an identical selection for Trigger. This ensures that the decode address
format matches trigger setup information.