Tektronix MDO3012, Руководство пользователя

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Acquire the Signal
SPI Bus
To acquire data from an SPI bus, you need to also set up these items:
1. If you selected SPI , push De fi ne Inputs and
the appropriate side menu choices.
Bus B1
SPI
De fi ne
Inputs
Thresholds Con fi gure B1 Label
SPI
Bus
Display
Event
Table
You can set the Framing to SS (Slave
Select) or to Idle Time.
You can assign the prede
fi ned SCLK , SS ,
MOSI , or MISO signals to any channel.
2. Push Con fi gure and the desired side menu
choices.
3. Push SCLK to set the edge of the signal to
match the SPI bus being acquired.
SCLK
4. Set the level of the SS, MOSI, and MISO
signals to match the SPI bus.
SS
Active
High
Active Low
Active High means that a signal is considered
active when the signal is greater than the
threshold value.
MOSI
Active
High
Active Low
Active Low means that the signal is
considered active when the signal is lower
than the threshold value.
MISO
Active
High
Active Low
-more-
1 0f 2
5. Use Multipurpose a to set the number of
bits of the SPI Word Size.
Word Size
(a) 8 bits
6. Push either side menu button to set the bit
order of the SPI bus.
Bit Order
MS First
Bit Order
LS First
MDO3000 Series Oscilloscopes User Manual 73