Tektronix MDO3012, Руководство пользователя

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Trigger Setup
With USB, CAN, CAN FD, or FlexRay, obtain a rolling window match by setting the Byte Offset in the Data menu to
Don't care .
Speci fi c byte matching (non-rolling window matching for a speci fi c position in the packet) for I
2
C, SPI,
USB, CAN, CAN FD, LIN, and FlexRay.
You can trigger on a speci fi c byte for I 2 C, SPI, CAN, CAN FD, LIN, and FlexRay in several ways:
For I
2
C and SPI, enter the number of bytes to match the number of bytes in the signal. Then use don't cares (X) to
mask the bytes that you are not interested in.
For I
2
C, push Trigger On on the lower menu to trigger on Address/Data . Push Address . On the side menu, push
Address , and turn
Multipurpose a and Multipurpose b as needed. Set the address to don't cares (X) if you want to
mask the address. The data will be matched starting at the fi rst byte without using a rolling window.
For USB, triggering occurs when the user-selected data input matches the data and quali fi er in the signal starting at
the byte offset. Set the number of bytes to match the number of bytes of interest. Use the data quali fi er to perform: =,
!=, <, >, >=, and <= operations.
For CAN and CAN FD triggering occurs when the user-selected data input matches the data and quali fi er in the signal
starting at the byte offset. Set the number of bytes to match the number of bytes of interest. Use the data quali fi er to
perform: =, !=, <, >, >=, and <= operations. Triggering on identi fi er and data always performs an exact match on
the speci
fi ed identi fi er and uses the selected quali fi er operation on the data, starting at the byte offset. Setting the
quali fi er to perform an “=” comparison will allow matching on up to 8 bytes of data. All other quali fi ers are limited to
4 bytes of speci fi ed data.
For LIN, triggering occurs when the user-selected data input matches the data and quali fi er in the signal starting with the
fi rst data byte. Set the number of bytes to match the number of bytes of interest. Use the data quali
fi er to perform: =, !=,
<, >, >=, <=, In Range, and Out of Range operations. Triggering on identi fi er and data always performs an exact match
on the speci fi ed identi fi er and uses the selected quali fi er operation on the data, starting with the fi rst data byte. Setting
the quali fi er to perform an “=” comparison will allow matching on up to 8 bytes of data. All other quali fi ers are limited
to 4 bytes of speci fi ed data. No rolling window is used.
For FlexRay and Ethernet, triggering occurs when the user-selected data input matches the data and quali fi er in the
signal starting at the byte offset. Set the number of bytes to match the number of bytes of interest. Use the data quali fi er
to perform: =, !=, <, >, >=, and <= operations. Triggering on identi fi er and data always matches the identi fi er and data
selected by the user, with the data starting at the fi rst byte. No rolling window is used.
Data Value Matching
You can trigger on a speci fi c data value for RS-232 bytes. If you de fi ned an end-of-packet character to use for RS-232 bus
decoding, you can use the same end-of-packet character as a data value for trigger data matching. To do so, choose the Tx
End of Packet or the Rx End of Packet character as the Trigger On selection.
You can also trigger on a speci fi c data value for other buses.
Parallel Bus Trigger Data Matching
Optimum parallel bus trigger performance is achieved by using only analog channels or only digital channels.
MDO3000 Series Oscilloscopes User Manual 99