Rohde & Schwarz MXO 4 Series - SPI Bus (Option R&S MXO4-K510); SPI Bus (Option R&SMXO4-K510); About the SPI Protocol

Protocol analysisMXO 4 Series
321User Manual 1335.5337.02 ─ 07
13.2 SPI bus (option R&S MXO4-K510)
The Serial Peripheral Interface SPI is used for communication with slow peripheral
devices, in particular, for transmission of data streams.
Required options and equipment
For performing SPI decode measurements, you need the following equipment:
●
MXO 4 with 4 channels. The channels can be a combination of the following:
– Analog channels (C1-C4)
– Logic channels (D0-D15) (requires option R&S MXO4-B1)
●
Option R&S MXO4-K510
13.2.1 About the SPI protocol
A 4-channel instrument is required for full support of the SPI protocol, or the MSO
option R&S MXO4-B1.
The Serial Peripheral Interface SPI is used for communication with slow peripheral
devices, in particular, for transmission of data streams.
The main characteristics of SPI are:
●
Main-subnode communication
●
No device addressing. The sub is accessed by a chip select, or sub select line.
●
No acknowledgment mechanism to confirm receipt of data
●
Duplex capability
Most SPI buses have four lines, two data and two control lines:
●
Clock line to all subs (SCLK)
●
Sub select or Chip select line (SS or CS)
●
Main data output, sub data input (MOSI or SDI)
●
Main data input, sub data output (MISO or SDO)
When the main generates a clock and selects a sub device, data can be transferred in
either or both directions simultaneously.
1
234567 0
CS
SCLK
MOSI
MISO
Shift Register
SPI Sub
1234567 0
CS
SCLK
MOSI
MISO
Shift Register
SPI Main
Figure 13-2: Simple configuration of SPI bus
SPI bus (option R&S MXO4-K510)