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Altera_Forum's avatar
Altera_Forum
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13 years ago

ARIA V memory resource usage

Hello,

I've created a memory block with megawizard for ARIA V component.

Memory size is : 524288bit

when I use the same data width for write and read (16bit for example) the resource usage is 64M10K but when I use different data widths (16bit and 32bit) resource usage is 128M10K.

can you explain why the Megawizard use double of the memory usage when I use different data widths?

thanks

4 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    Look at device data regarding memory support for bitwidth. A single block may in your case not support 32 bits in which case two blocks will be in parallel. It may also depend if it read only or read/write.

  • Altera_Forum's avatar
    Altera_Forum
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    I am using Simple Dual-Port RAM with 1 read and 1 write port but with different clocks (read clock, write clock) and different bus widths.

    i am looking at "M10K Block Mixed-Width Configurations (Simple Dual-Port RAM Mode)" table and it says it supports write 512x16 and read 256x32.

    Can you please explain?
  • Altera_Forum's avatar
    Altera_Forum
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    Your requirement is 524288 bits i.e. 512kbits

    It looks like in your case each block supports only 8k either as 512x16 or 256x32 rather than 10k.

    Thus at 16 or 32 bits your requirement translates to 512k/8k = 64 blocks.

    So if your write is 16 bits and read is 32 bits I don't expect doubling of blocks.

    But look in the corners of data sheet regarding any hidden exceptions. It could be what you read is for write only read only ports and that your configuration is mixed on one port.
  • Altera_Forum's avatar
    Altera_Forum
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    Perhaps the memory block is just being duplicated ?

    If there is enough memory on the device this might be done in order to remove some logic.