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Altera_Forum
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11 years ago

I2C inout simulation

I am using VHDL to try and simulate an I2C master and slave. My slave has an inout port named i2c_sda. My master has a in port named i2c_sda_in and a output port named i2c_sda_out. In...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
11 years ago

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  • in both devices (master and slave) detect a logic 1 by using the statement "if(signal = '1' or signal='H')", instead of just saying "if(signal = '1')"; this will make sure you detect a logic 1 regardless of how you drive it

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Alternatively you can use the To_X01() function from std_logic_1164. I think it makes it easier to read and maintain than having to double all the ifs in the code. This function converts a 'H' to a '1' and a 'L' to a '0'. It is also recognized in the synthesizer so it can be kept in the final code.