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Altera_Forum
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16 years ago

JTAG can’t find device

Hi all, I am a beginner of Altera's device. Today, When I use the JTAG mode of Quartus’ programmer to configure the device EP3C5E144, the programmer always says “Unable to scan device chain. Can...
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Altera_Forum
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16 years ago

The Vccpd = Vccio1A = 2.5V

The program connector is powered by V_3.3

These should be the same (either V_3.3 or 2.5V).

nSTATUS and nCONFIG and CONFIG_DONE should be pulled-up to Vccpgm, which is 3.3Vcc, not V_3.3.

Maybe these are supposed to be the same, but in your schematic the labels differ.

Pull-up JTAG to Vccpd.

Pull-up other programming pins to Vccpgm.

Good luck, Ton