The Configuration Problem Solver

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Is the data on DOUT the correct data?

Yes, the preamble is observed. No, it is incorrect.

The first data that should appear on the DOUT pin is the Preamble <0010>, MSB first. The Preamble typically follows a fill byte <11111111> and is followed by the 24 bit LengthCount, the first nibble of which is usually <0000>. Therefore, the first two bytes should be <1111 1111 0010 0000>, MSB first. The Preamble is the all important part. The FPGA will not begin the configuration process until this sequence is observed. The LengthCount does not necessarily have to start with zero <0000>. Record the data that you observe on DOUT and compare it with that of your bitstream file to determine if it is correct.