Serial bus analysis
R&S
®
RTA4000
265
User Manual 1335.7898.02 ─ 08
● "Bit <x>": a specified bit inside the message
● "Serial Pattern": a bit pattern in the message
6. If "Serial Pattern" is selected, the SPI trigger setup dialog expands to define the
serial pattern.
SPI trigger settings
The trigger settings are shown in the dialog below the bus configuration settings. In the
trigger menu, you select the trigger source, and open or close the setup dialog box.
Figure 13-6: SPI trigger menu
Figure 13-7: SPI trigger settings with an example of an SPI serial pattern
9
= Hex value of the 1
st
nibble, with the binary value 1001
$ (blue) = Hex value of the 3
rd
nibble, which includes some "X" bits. The blue color indicates that the key-
pad is active for this nibble.
X (white) = The 6
th
nibble is a "don't care" nibble, as it consists of "X" bits, only
$ (white) = The 7
th
nibble is only half contained in the specified pattern length of 26 bits
X (gray) = The 8
th
nibble is not contained in the specified pattern
SPI bus (option R&S
RTA-K1)
