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Altera_Forum's avatar
Altera_Forum
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14 years ago

CycloneIII and CycloneIV pin to pin compatible?

Hello everybody, i have a simple question, i want to use EP3C25 - 144 pin EQFP package in my project and there is also EP4C22 - 144 pin EQFP package fpga. are these pin to pin compati...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
14 years ago

More complex answer: Maybe

First of all, I don't think there is an EP4C22. Are you referring to the EP4CE22? I would assume you are as the EP4CGX22 is not available in the 144 pin EQFP package.

I haven't compared the specific parts in question, but in my limited experience I have found the Cyclone III and Cyclone IV E parts to be extremely similar. In the two cases where I compared, there was only a couple pins different between two similar parts from each family. If you avoid using these pins in your design it may be possible to make a board compatible with both.

Your best bet is to compare the pin outs yourself. If they are similar, try compiling your Quartus project for both parts to make sure there are no errors. Make sure you have a backup first. Answer "no" when you switch the device in Quartus and it asks you if you want to reset all I/O assignments. If you do get an error, you may be able to tweak your pinout to make it compatible with both parts.