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Altera_Forum's avatar
Altera_Forum
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9 years ago

Cyclone V A9 DDR3 calibration fail no reboot ,but JTAG is OK

Dear All, help me analysis.

I have a custom board with cyclonev and DDR3 (mt41j256m16tw-107it. In quartus ii v15.1.0 (64bit) I created Uniphy external DDR3;when I download sof file to FPGA through JTAG, calibration is ok,

,after i program FPGA PROM, turn off the power,when turn on power, calibration fail.

drr3 config as flowe:

i have tried many times, the voltage supply the voltage supply is ok

VddQ 1.35V

VTT VREF 0.678V

1 Reply

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    9 years ago

    How soon after power-up/configuration is the calibration done? Are the supplies stable at that point?

    Hold the Phy in reset for longer after power-up before allowing calibration to proceed.

    Cheers,

    Alex