MSEL:1001:AS STANDARD 3.3V
It works normally when I download the .sof file.
I replaced FLASH, FPGA, USB blaster cable and computer, and the same phenomenon still exists.
The following picture shows the successful download interface. At the same time, I collected the DCLK waveform with an oscilloscope, which has a clock signal.
When the PCB is re-powered, the FLASH pins have signals except DCLK which is always high.
Please refer to Cyclone IV handbook for configuring using serial configuration devices. Make sure to follow the suggested steps as stated in the handbook;
Can you try to remove the resistor on the DATA line?
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