How do I get the address of the PHY port on an EP3C120 dev board?

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I got this board (http://www.altera.com/products/devkits/altera/kit-cyc3-dsp.html) and on it is exactly the Marvell 88E1111 chip

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Page 13 of the schematic has the PHY, with

CONFIG[0] = LED_RX = 010b => PHY address [2:0] = 010b

CONFIG[1] = LED_LINK10 = 110b => PHY address [4:3] = 10b

So PHY address [4:0] = 10010b = 12h

The PHY is configured to use MDIO mode, so this is the address you need to use along with the MDIO bus protocol (rather than using I2C).

Cheers,

Dave