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Altera_Forum
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15 years ago

I2C loopback on Max II

Hi, I'm trying to figure out a way to do a I2C loopback test. How do I handle the bidirectional data, without actually implementing the logic of reading the R/W* bit on the address sent out? I ...
Altera_Forum's avatar
Altera_Forum
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15 years ago

I don't exactly undertand what an i2c loopback test is. But I doubt, that you can operate an I2C interface without evaluating the direction information, respectively the adressing and read/write state.

A digital bidirectional buffer, e.g. a HC245 device, can't work without DIR control. Special I2C buffers are either utilizing analog bus swiches or an analog direction sense detector, both aren't available with CPLD or FPGA.