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Altera_Forum
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16 years ago

PCI Express Tx interface gets stalled

Hi, I'm still trying to send data (A/D samples) from my PCI Express endpoint (S4 GX Dev. Kit. -> Hard IP) to the root port memory (RAM). I'm able to receive data from the root port, and also...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

Thanks BrettFavre, it seems you are right, I'm running out of posted data credits! Bevore I sent the first packet I had 128 posted data credits (tx_cred=0x080fb0407), and after the packet has been transmitted to the Megafunction the value was zero (tx_cred=0x080fb0007).

The time between two packets is longer than it takes to transmit the package (512 DW payload) to the MegaFunction, so how long does it take before I can send the next package? How can I get more/new posted data credits?