Programmable Devices
CPLDs, FPGAs, SoC FPGAs, Configuration, and Transceivers

SDRAM DQ pin

Altera_Forum
Honored Contributor II
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Could anyone tell me whether I can connect the SDRAM DQ pin to FPGA's normal IO not DQS or DQ?What will it happen?

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Altera_Forum
Honored Contributor II
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As long as you do not violate the specs of the SDRAM, you should be ok. For example, if you SDRAM VDD is 1.8V, then you should have the FPGA driving pin located in a bank with 1.8V or 1.5V VCCIO. I am assuming these DQ pins will not be used for regular data interface, since you do need to use the FPGA IO pins reserved for DQ/DQS functionality to properly interfae to your DRAM.

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Altera_Forum
Honored Contributor II
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Okey,ironmoose,thanks for your explanation:-),I still have the question whether it is okey if I use two separated BANK to drive the DQ?

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Altera_Forum
Honored Contributor II
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FPGA DQ/DQS designation is for DDRx SDRAM. Do you have DDRx SDRAM or SDR SDRAM?

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Altera_Forum
Honored Contributor II
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cioma,I use SDR sdram now.

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Altera_Forum
Honored Contributor II
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In that case you don't care about DQ/DQS pins, simply connect you SDR SDRAM to one or several neighbouring banks.

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Altera_Forum
Honored Contributor II
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hi,would you please tell me which pins are assigned to ddr sdram controller,b'se it has lot of pins .is any fixed pins are assigned in fpga for sdram access,please explain(i use cyclone ii(de2))

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