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Altera_Forum's avatar
Altera_Forum
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15 years ago

JTAG did not work.

Hello all. We are make PCIe board at Aria GX2. It's highly simplified kit from Altera. The DC/DC is working very good. But JTAGs didn't work at all.

I can see signals at JTAG TDI, TMS, TCK but nothing at TDO. I'm try to connect TDI to MAX-II and ArriaGX-II in parallel and disconnect MAX TDO from Arria TDI. But I can't see signals at MAX TDO and Attia TDO.

I'm use 2.5v to supply MAX and Arria JTAG banks.

MSELs connected to ground. nConfig and nStatus I'm pull up.

6 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    --- Quote Start ---

    This is a test.

    --- Quote End ---

    You test is ok. Jtag is't ok.
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    The JTAG tap controller enables TDO, when it's state advances to a SHIFT_DR or SHIFT_IR state. Never reaching this state (respectively not seeing TDO activated) in standard JTAG scan and similar actions most likely indicates:

    - device is held in reset, because one of the supply voltages required for JTAG operation (see the manual for details) is below it's reset threshold

    - TMS, TCK or TDO are not connected correctly
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    --- Quote Start ---

    The JTAG tap controller enables TDO, when it's state advances to a SHIFT_DR or SHIFT_IR state. Never reaching this state (respectively not seeing TDO activated) in standard JTAG scan and similar actions most likely indicates:

    - device is held in reset, because one of the supply voltages required for JTAG operation (see the manual for details)

    --- Quote End ---

    Volatges is ok. Core - ok and IO Bank is ok.

    --- Quote Start ---

    is below it's reset threshold

    - TMS, TCK or TDO are not connected correctly

    --- Quote End ---

    I'm check this many times. It's ok. I'm even solder wire direct from JTAG pin to closed via from Arria chip.
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    According to the device manual, POR is monitoring these supply voltages:

    VCCCB, VCCA_PLL, VCC, VCCPD, and VCCIO for I/O banks 3C or 8C
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    --- Quote Start ---

    According to the device manual, POR is monitoring these supply voltages:

    VCCCB, VCCA_PLL, VCC, VCCPD, and VCCIO for I/O banks 3C or 8C

    --- Quote End ---

    All voltages, pll, etc, is ok.