Befor I set Reg0x41=0x10 to power up the AD9889B, the Reg0x42=0x60;
But after powered up, the Reg0x42=0x40.Unless HPD pull down again, Reg0x42 always value 0x40; WHY?
The AD9889B stays in power-down mode until you get HPD. You can't program the part without HPD.
AD9889B is not recommended for new designs. You should use ADV7511 which can be setup to not need HPD.
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