Why do some scopes trigger and/or decode I2C serial data as a 7 bit address and others as an 8 bit address? Why do some scopes trigger and/or decode extended I2C addresses as a 10 bit address versus a 16 bit address?
There are two ways to group I2C addresses for decoding: in 7 bits plus a read or write (R/W) bit scheme, and in 8 bits [a byte], where the R/W bit is included as part of the address. The 7 bit address scheme is the specified I2C Standard followed by firmware and software design engineers.
The 8 bit addressing scheme is followed by many IC manufacturers and hardware design engineers. The Tektronix DPO4000 series oscilloscope follows the adopted I2C Standard [7 bit] to trigger on and decode the I2Cserial data address in the packet. Examples showing you how to convert between a 7 bit-to-8 bit I2C address scheme follow.
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FAQ ID 62396View all FAQs »