Programmable Devices
CPLDs, FPGAs, SoC FPGAs, Configuration, and Transceivers
20403 Discussions

Cyclone IV E configuration cycle never starts



I have trouble in configure my Cyclone IV E FPGA, (The smallest FBGA 256 commercial variant speed grade 8), using the AS, Active Serial programming method. 

Here are the implementation details:

  1. Using a EPSC128 SPI configuration device. (+3.0V Vcc) and USB Byte Blaster. The Quartus II programmer detects device ID(0x18) and the SPI Flash gets correctly programmed according to the programmer GUI.
  2. The FPGA MSEL[2..0] pins are put as spec. to [011]. Configuration pins pulled up/down according to spec. except the nSTATUS signal.
  3. The 3.0V Vcc ramp up time is ~ 1.0 ms.

When I’m measure with my oscilloscope I can see that the FPGA configuration cycle never initiates. The FPGA should set the nCS logic low and start the DCLK but that never happens.

One thing I have noticed is that the nSTATUS pin is NOT pulled up. The spec. states it should. From what I understand from the spec. the nSTATUS toggles to indicate that the FPGA POR is released. (Power Supplies ramped up and are stable). Is this nSTATUS signal just a signal that you can monitor or must it indeed be pulled up.

I have another type of circuit board, (a Cyclone IV E and the same SPI Flash), and I moved away the nSTATUS pull up resistor on that board. Still it is no problem to configure the FPGA from the SPI Flash, so I am little bit confused about the need of nSTATUS pull up resistor or not.

Anyone else, of all you good engineers out there, that have had this issue?

Best regards


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Thank you for contacting Intel community.

Per my understanding, you are having problem with Cyclone IV configuration. Did you follow the configuration guidelines?

Refer to chapter 8 in the link below;



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We do not receive any response from you to the previous answer that I have provided. This thread will be transitioned to community support. If you have a new question, feel free to open a new thread to get the support from Intel experts. Otherwise, the community users will continue to help you on this thread. Thank you

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