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Altera_Forum
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15 years ago

Error: Can't access JTAG chain

When i try to program the FPGA cyclone III i get this error : error: can't access jtag chain error: operation failed. I am using a FPGA cyclone III .I would be able to program it a few months...
Altera_Forum's avatar
Altera_Forum
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14 years ago

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Check the JTAG signals. Especially the clock, that must have clean edges.

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Bad news for me! The JTAG's TCK pin has no signal at all. When I connect the USB-BLASTER to the JTAG's ten pins, the TCK is always 3.3v,and without the USB-BLASTER,it is always 0v.

What's the real signal of the TCK as it should be? The TCK signal is given by the FPGA or the usb-blaster?