I have the AD9387NK_ADV7520NK_Programming_Guide_Rev0_feb_2008.pdf. The default I2C addresses are indicated in Table 2 of this documents (page 10) and I can't find the chip on these addresses. If I scan the I2C bus I find the chip with following addresses: 0x38 0x39 0x3C and 0x3F Do you know what is the problem or do I need a new Programming Guide?
Our documentation uses 8-bit addressing for I2C addresses. It may be that you are using 7-bit addressing.