Hi,
It is not "I2C", because I2C uses 9 clocks per byte. But in your picture there are just 8 clocks per byte.
I don't think it is following a specific protocol
You cant say if this is a "protocol" or not, as long as you don't recognize any dedicated pieces of data and frames.
Maybe you mix the phrases "interface" and "protocol".
A
protocol is the
language, it defines the meaning of the data.
An
interface is the method, how you
transport the informations. (Speaking vs writing)
With your scope pictures you may find out what "interface" it is, but it will be hard to find out what protocol it is:
From the pictures you see:
* it is two wire
* it is synchronous
* it is 8 clocks per byte
* a data line
* a clock line
* the timing when "data" is pushed on the line with respect to clock
* the voltage levels
(It may be USART or SPI...)
But you don't (easily) see protocol related specifications like:
* whether the data and clock channels are bidirectional
* if the idle timing is a part of the protocol
* the meaning of each byte
...
Klaus