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Altera_Forum's avatar
Altera_Forum
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14 years ago

I/O asignment using Problem

Error: Can't place output or bidirectional pin VGA_G[2] in input pin location A14

Error: Can't place output or bidirectional pin VGA_G[1] in input pin location B14

...etc

I found that the problem only happend in using bidirection or outputon CLK pins.

Is that means Clock pins can only use on input pins?

By the way, I also want to know if I using CLK as input data,Bad?

will Other pins do same problem?

2 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    14 years ago

    Apparently you tried to use a dedicated input pin as output. There are only a few pins, that aren't suitable as outputs. As the hardware manual, pinout files and Pin Planner tool clarify, clock inputs can be still uitilzed as logic inputs.

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    14 years ago

    HaHa, Thank you Guru!

    I found a document PCG-01003[1].pdf at atera's website.

    I got to change my design includes PCB layout.