how to drive high('b1) bydefault if nobody is driving the interface signal

[rexjohn4u]

Hello,

I am trying to implement an I2C interface. SCL and SDA signals are on high('b1) state if in stop/inactive state. How can i model the same?

Later if i want to drive 'b0 or 'b1 from the driver, it should not throw error. And if i am not driving any value, it should go back to high('b1) state

Please explain what is 'pullup" premitive and how it is used

 

[FvM]

I presume you know that real I2C hardware depends on pull-up resistors, so you are apparently asking how to handle it in simulation.

Verilog has net drive strength specifications, a pull1 drive strength should work in this case. It will be overriden by the default strong0 drive sttrength of the open drain SDA and SCL driver.

 

[rca]

In simulation the I2C pads, should be connected to "H" state, and your chip could only drive '0', never drive '1' in I2C protocol, the pull-up (external or internal in your pads) will rise the line.

 

[FvM]

In simulation the I2C pads, should be connected to "H" state

I presume you are assuming VHDl std_logic type. Verilog has no 'H' state.