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Altera_Forum
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20 years ago

Parallel Flash Problems

I have searched tediously through the forums for any help on this, and have tried a lot of different things. I am using the same Flash chip as on the NIOS II Cyclone II Eval board on a custom d...
Altera_Forum's avatar
Altera_Forum
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20 years ago

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originally posted by hippo@Feb 22 2006, 08:35 PM

you can try download a program into dram, and try out flash read write from dram. so that you can isolate if it is a jtag problem or others.

you can try to set io pin current stength to minimum. the jtag singal is weak. you should also try add series terminator / pull high to jtag signals.

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Hey hippo; I don&#39;t see how setting the current strength to minimum will help JTAG? I can&#39;t set the signal strengths on the JTAG pins (I don&#39;t think). And I don&#39;t think JTAG is the problem since I Can download code and run from DRAM without problem, as well as use Signal Tap. Also, I have tried what you said, reading/writing Flash from DRAM, and similar errors happen; I can confirm that errors I see with SignalTap are the same errors detected in code.

I have also replaced the chip, so it&#39;s not the chip... and the circuit is a duplicate of what is on the Cyclone II dev board (just for some more info)