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Altera_Forum's avatar
Altera_Forum
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15 years ago

Input pins are driven down

Hello, I wish everyone have happy new year.

In my case, it's not.

I have connected input pins of CPLD(MAX II, EPM570C5N) and CMOS image sensor output pins.

But, there are a problem with them except one of these connection.

The problem is that:

VIO of CMOS sensor is 3V3 and it is same as the Vcc and VCCIO of MAX II.

Now, the highest voltage of output of CMOS sensor was 3V when the output pins free.

But after I have connected the I/Os of CPLD and camera, the wire can't be driven so high and the highest voltage of the wire is 0.3V or so, except one connection, that was to 3V3 and there are signal.

Another pin was driven Low constantly.

I have located input pin to correct location with Pinplanner.

But the pins are driven low. How should I do with setting of Quartus II?

My Quartus II is 10.0 web edition.

Thanks!!

6 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    I haven't resolved it yet, and now I wonder if there is some tips, for example, just not write with USB-Blaster to MAX II after edit with PinPlanner and I have to do something after setting the pin assign with PinPlanner, or there is an important setting at programming tool.

    Once, I have doubted that my assignment setting of PinPlanner was mistaken, and my device was broken, but both was not.

    Because after clearing the assignment setting and changing the device, I set assignments of PinPlanner and written to another device.

    But it don't works properly.

    Does anyone have ideas?

    Please help!
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    The programming mode is JTAG, and Quartus II version is 10.0.

    My USB-Blaster is from terasic.
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    --- Quote Start ---

    The programming mode is JTAG, and Quartus II version is 10.0.

    My USB-Blaster is from terasic.

    --- Quote End ---

    Hi,

    are you sure that the programming is succesful ? Have a look into the <project_name>.pin file and double check your pin assignments.

    Quartus has a default setting for unused pins, which is "Output driven ground". You should change the setting to " As tri-stated input with weak-pull up" and run a new compilation.

    You can change the setting by:

    Assignments -> Device -> Device and pin options -> unused pins

    Kind regards

    GPK
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    --- Quote Start ---

    are you sure that the programming is succesful ?

    --- Quote End ---

    Having pins acting as output unintentionally can be only explained by a wrong pin assignment, programming a wrong configuration stream, or a defective device.
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    OK,

    I will double and triple check for it immediately,

    but I had set unused pins as input tri-stated with weak pull-up pin,

    but the problem occurred.

    I have no idea why the pin is driven down.

    If my config is wrong, the pin should be weak pulled-up.

    Thanks a lot!
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    Thank you all,

    I doubted some invisible settings or so,

    and make a new project and import same settings by hand.

    My problem was resolved. Perhaps I have some edited confusing setting, or it came from my stupid and hard to find mistake, or bugs of Quartus II 10.0.

    Anyway, after the idea, rebuilding as new project, I could this very easily.

    Thanks.