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Altera_Forum
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17 years ago

I2C Controller

Hi, I have an FPGA design that relies on a couple "constants" in registers that I would like to make changeable over an I2C interface. Does anyone know if there is a standalone core I could us...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
17 years ago

With FX2, an I2C controller is already present while SPI has to be emulated by I/O bit-banging. Thus I2C needs less resources at the uP side and can operate faster. If the FPGA is intended to be configured by the uP through passive serial, you need to create an SPI-like interface anyway and can use it for runtime communication as well.

SPI at the FPGA side is actually somewhat more simple than I2C, basically a shift register only.