UNI-T UPO2000CS Series, Руководство пользователя

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UPO2000CS series User Manual
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The above picture is the I2C bus protocol diagram of a 7-bit address. After starting, the host transmits the address information and
read-write direction information in the first byte (normally, 0 means write and 1 means read). After the slave send the respond signals, the
data between the host and the slave begins transmitting. The host sends stop signal to end this communication after finishing the data
transmission.
Handling 10 bit address is a little different from 7 bit address. The address information is made of the first byte after the start bit. The seven
bits of the first byte is 11110XX. The XX is the two top bits among 10 bits. The eighth bit of the first byte is R/W which means read/write
direction (0 is read, and 1 is write). The second byte is the remaining eight bits among 10 bits. If R/W bit is 1, the next byte is the data
transmitted by the slave to the host.
The following are the I2C protocol functions:
I2C
：
I2C Start Trigger
Press the DECODE button at the right corner. Then press the TYPE option key to open protocol type list. Rotate
Multipurpose knob to select the SPI protocol mode. Press Multipurpose knob to start the SPI protocol mode.
SCL: Select clock source
Press this option key and the present clock source font becomes green. Press the SCL button again to switch any
channel among CH1-CH4 as clock source. The corresponding logic level can be adjusted when the corresponding signal
source is selected. The way of adjusting is the same with that of trigger level. To avoid the effect of signal noise, it is
suggested that the comparative level should be set in the waveform center area to obtain accurate results. Press the
SCLK EDGE button to set the clock source as rising edge or falling edge.
SDA: Select data source
Press this option key and the present clock source font becomes green. Press the SDA button again to switch any
channel among CH1-CH4 as clock source. The logic level can be adjusted when the corresponding signal source is
selected. The way of adjusting is the same with that of trigger level. To avoid the effect of signal noise, it is suggested
that the comparative level should be set in the waveform center area to obtain the accurate captured result.
Condition: Trigger Condition Selection
Press this option button and the trigger timing selection will pop up. The following are the trigger timing conditions: