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TBake8's avatar
TBake8
Icon for New Contributor rankNew Contributor
6 years ago

Determining Failing State of Cyclone IV E Between Startup Reset and Configuration

Hi I'm developing my own FPGA board using a Cyclone IV E EP4CE10E22C8N but when I use the USB blaster JTAG, it says it cannot scan the device chain. I have measured the configuration pin voltages (nS...
AnandRaj_S_Intel's avatar
AnandRaj_S_Intel
Icon for Regular Contributor rankRegular Contributor
6 years ago

Hi Ted,

As per the information provided, the POR requirement looks fine. Now we should focus on JTAG, regulator & passive component on board.

  1. Try to have 1K ohm resistors for JTAG header circuitry, I know Resistor value can vary from 1 k to 10 k, depending on the hardware it may change, try changing the values.
  2. What is the supply current of the 5V main supply ?? Because nConfig voltage as dropped, Voltage may drop if it can't drive enough current and ensuring power remains the same.
  3. Can you replace the 4K7ohm resistor on nConfig can check??
  4. Also, check power signals from the source till the destination pins(including regulator & passive component).

Regards

Anand