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1130 Discussions

SD Audio demonstration - code confusion

Honored Contributor II

When compiling the SD Card Audio demonstration (from the FTP site) there is a problem with the I2C master clock.  


It is line 277:  

// I2C Tri-inout 

assign I2C_CLK = SCL_OE_N ? 1'bz : SCL ; 


The error message is: "Error: The pin "I2C_CLK" has multiple drivers due to the non-tri-state driver "I2C_AV_Config:u1|I2C_Controller:u0|I2C_SCLK"  


I am just learning VHDL, and what I understand is that the master clock is set to High z, which disconnects the master clock from the system which is why I am getting the error message. IF I comment out that line then I am able to compile the code fine. 


However, when I connect my SD card with a few wav files and load the .sof to the FPGA nothing happens. Since I grabbed the demonstration from the FTP site I am assuming the code is up to date, and the I2C_CLK line was necessary. 


I have spent a couple of hours looking at the code and while I understand individual pieces better, I do not understand the system as a whole. Any ideas of what is wrong, or guides that I can read to help troubleshoot my problem? 


Edit: I don't know if this information would help but i found it interesting. Just tried and the TV Decoder demonstration and it worked (minus the video because I do not have a cable to connect the video port of the dvd player to the composite port on the DE2 board). I find it interesting because it uses I2C as well, having the same I2C_AV_CONFIG file and they look identical. However, the difference between them was the audio demonstration set the master clock and data inouts are set to High z.
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2 Replies
Honored Contributor II

I don't need someone to just give me an answer, if there is any other information needed I can try to provide it.  


Or if someone can give me a hint, or some type of documentation that would help point me in the right direction I would very much appreciate it.
Honored Contributor II

I'm facing the same problem. 

Did you get any solution regarding I2C_CLK error..? 


Please reply. Its urgent. 

Thank you in advance..!!