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TBake8
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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...
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TBake8
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6 years ago

Hi Anand,

I have changed the resistors on the jtag header (R43, 44, 45) to 1k. I tested the device again, but not able to scan device chain.

I am fairly confident the 5V supply is ok, it is an Agilent E3631A which I have set with current protection at 500mA. The powersupply says about 50-60mA are being source from the 5V supply.

I replaced the 4k7 resistor on nConfig with a 10k resistor and the voltage read 0.8V. I then replaced it again with a 1k resistor and it now reads 2V. Still no luck.

I have checked continuity between voltage supplies and the FPGA pins - they are all fine.

Regards