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annul signals in megafuntions?

Altera_Forum
Honored Contributor II
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Hello 

 

I Am using instantation megafuntions in vhdl. And generate it, many pins. Is possible to annul signals that are not in use of these megafunctions? 

 

Regards and Thanks
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Altera_Forum
Honored Contributor II
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What do you mean by annul? 

You can connect the pins to any legal signal - but setting a pin to a constant value may affect functionality, depending on the pin. Why not specify what you are trying to do?
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Altera_Forum
Honored Contributor II
618 Views

Hello Tricky, First pardon for my english, it is not my native language. 

 

I am trying to do a board with a cyclone the III or IV, for an university work. And it has to include the basic controllers, Bus PCI, controllers of memory SDRAM and Flash.  

I start by compiling only the megafunction of the bus PCI (pci_mt32) and appear 217 pines in the compilation (quartus 12.1) and 185 pines (quartus 9.1). They are a lots. I readed that for a basic bus with 47 or 49 pines is enough. I suppose that they are exceed pines and I do not need to use all the signals. Or am I doing something badly?  

 

Regards 

 

https://www.alteraforum.com/forum/attachment.php?attachmentid=8578 https://www.alteraforum.com/forum/attachment.php?attachmentid=8579 https://www.alteraforum.com/forum/attachment.php?attachmentid=8580
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Altera_Forum
Honored Contributor II
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You need to read the specs for what all the pins do to see if it is safe to tie them to '0'. '1' or leave them open.

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