Loading ...
Loading ...
Loading ...
Serial Bus Analysis
R&S
®
RTB2000
178User Manual 1333.1611.02 ─ 03
Remote command:
TRIGger:A:SPI:MODE on page 378
Bit Offset
Specifies the number of bits before the first bit of the pattern. These bits are ignored.
The first bit after frame start is Bit 1. For example, with bit offset = 2, Bit 1 and Bit 2 are
ignored, and the pattern starts with Bit 3.
If "SPI Trigger" is set to "Bit <x>", the trigger is set to the next bit that follows the offset
bits. For example, if the bit offset is 4, the instrument triggers on the start of the 5th bit.
Remote command:
TRIGger:A:SPI:POFFset on page 380
Number of Bits
Defines the length of the serial pattern in bits.
Note: Entering data bits beyond the specified length of the pattern automatically
adjusts the "Number of Bits" to include all entered bits.
Remote command:
TRIGger:A:SPI:PLENgth on page 379
Data
Specifies the data pattern if "SPI Trigger" is set to "Serial Pattern". When the instru-
ment detects the specified data pattern, it sets the trigger to the first bit of this pattern.
An example of pattern definition is shown in
Figure 12-5.
To enter the binary value of any bit, tap this bit. To enter the hexadecimal value, tap
one of the nibbles (half byte) in the lower data line.
If a nibble (half byte) contains 1, 2 or 3 "X" bits (don't care), the nibble value is repre-
sented by the character "$". If all 4 bits of a nibble are "X", the nibble itself is "don't
care", represented by the character "X".
Remote command:
TRIGger:A:SPI:PATTern on page 379
12.2.4 SPI/SSPI Decode Results
When the configuration of the serial bus is complete, the signal can be decoded:
1. In the "Bus" menu, enable "Decode".
2. In the "Display" menu, select the result display settings.
See
Chapter 12.1.2, "Display Settings", on page 167.
3. In the "Bus Table" menu, enable the "Bus Table". Adjust the table settings.
See also: Chapter 12.1.3, "Bus Table: Decode Results", on page 167
The instrument captures and decodes the signal according to the protocol definition
and the configuration settings.
SPI/SSPI Bus (Option R&S RTB-K1)
Loading ...
Loading ...
Loading ...