Recently I'm coding an I2C slave interface using HDL(verilog). In I2C specification, there is only two line: SCL and SDA. I've searched a lot of example design, they all use a higher speed clock to sample SCL and SDA, and then judge Start/Stop condition. The internal logic are also work at this higher speed clock.
My question is: can I code an I2C interface logic which only use SCL and SDA? If there is no higher speed clock, could I2C controller work well?
Many thanks if any sample code is available!
Thanks a lot!