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Altera_Forum
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14 years ago

PCIe Memory Write Transaction

Hi, I am facing an issue while performing memory write transaction with payload more than 128Bytes from root to endpoint. Write transaction with less than 128Bytes are completed easily. I have ...
Altera_Forum's avatar
Altera_Forum
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14 years ago

128 bytes is the likely limit for a single PCIe memory transfer.

I don't know if it is a hard limit in the PCIe protocol, or whether the ends can negotiate a different value.

However it is probably getting near to the point of diminishing returns.

Remember, a PCIe request is actually an HDLC frame - cannot be actioned until the crc has been checked (etc).