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Old 04-10-2006, 01:33 PM
Prakash
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Default unused pins

I try to port processor in xilinx FPGA. The processor code does 've
more inputs, outputs, buffers declared in entity. Now while pin
assignment in ucf file, if suppose I use only some and left others,
without assigning at all , will the ISE assign those left signals to
pins automatically. Iam trying to download to development board, which
is assigned for some processor/logic. If suppose the tool automatically
assign some pins which is not intended, it may cause board problems. Am
I right, give some insight,
Prakash

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Old 04-10-2006, 01:47 PM
bjzhangwn
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Default Re: unused pins

In general ,I think the tool will aotumatically remove the unused pins
in the designs,but we shuld let the unused pins have the proper
state,for example iin the ddr sdram if the DQM signals have hardly
attached in the borad,if I don't use it in some circumstance,so we must
let if high,and if we don't make it the proper state,and the data will
be wrong,I don't know if I am right.

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Old 04-10-2006, 02:34 PM
motty
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Default Re: unused pins

You can always build it and see. Use the floorplanner tool to see what
external pins are there. The EDK will apparently place and route all
signals in its external port list (that makes sense). I doubt the ISE
will route anything that is not being used.

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Old 04-10-2006, 02:37 PM
Prakash
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Default Re: unused pins

What I thought of unused pins is to make some state, but while
assigning package pins in ISE, in PACE, I couldnt assign nets to pins I
need. I could see only banks(bank0,1,,) not AJ15/AC4.... . How to
assign nets to pins graphically rather UCF file.
Where Iam wrong,
Prakash

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