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Altera_Forum's avatar
Altera_Forum
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17 years ago

Bidirectional pin help!

Hi, I have a I2C code which sends write only data from my fpga to the audio codec on the board. The code is fine apart from one part After 8 bits of transfered data from the fpga to the au...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
17 years ago

I don't exactly your problem. Yes, SDA (and in general also SCL) are bidirectional pins, that means Verilog inout type. According to the I2C specifications, they are operated as open drain pins: either 'Z' or '0', but never '1' as output state. You can consult example designs for Dev. Kits with I2C from Altera or Terasic.