6.3 SPI Decode
SPI interface is a kind of synchronous serial peripheral interface, which can make the host and all kinds of peripheral
equipment undertake communication through the serial methods. It is a kind of synchronous communication bus of full
duplex. It usually uses four signal lines: MOSI: the host data output, the slave data input; MISO: the host data input, the
slave data output; SCLK: clock signal generated by the host; CS: the slave chip selection enable signal.
SPI interface is mainly used for synchronous serial data transmission between the host and low speed peripheral devices.
Under the shift pulse of the host, the data is transmitted in bits, that is to say, higher bit first and then lower bit. Since the
SPI interface does not need to look for the slave address and is full duplex communication, the protocol itself is relatively
simple and therefore is widely used. SPI protocol transmission is shown in the following picture:
Note: At least 3 output channels are required. Therefore, this function is only available on the 4-channel product of
UPO2000E series oscilloscopes.
SPI Selection:
Press DECODE type , and select SPI by the Multipurpose knob. You can also switch the trigger type by consecutively
pressing the type key, then press the Multipurpose knob to confirm.
CS Source:
Press the CS source button to set any of CH1~CH4 as the chip select input of the SPI decoded signal.
SCLK Source:
Press the SCLK source button to set any of CH1~CH4 as the clock input of the SPI decoded signal.
MOSI Source:
Press the MOSI source button to set any of CH1~CH4 as the data MOSI input of the SPI decoded signal.
MISO Source:
Press the MISO source button to set any of CH1~CH4 as the data MISO input of the SPI decoded signal.
CS Polarity:
Press PgDn CS polarity , to set the polarity of the chip select signal: positive polarity or negative polarity.
Positive polarity: Valid when the chip select signal is positive.
Negative polarity: Valid when the chip select signal is negative.
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Summary of Contents for UPO2000E Series
Page 1: ...UPO2000E Series Ultra Phosphor Oscilloscope User Manual...
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