PCIe显卡，16对 Receive 信号是闲置的吗？

Quantum_

1. x16 的显卡， 共有HSI(0)n/p ~ HSI(15)n/p 16对Receive信号（显卡到CPU）.
2. 显卡只是一个输出设备，只接收CPU的输出， 并不需要与CPU高速交互。
3. 那么， 第1点描述的16对线， 是否就一直是闲置的？ (这么浪费，有点不可思议！特发此问）

5 C6 z( d6 F; y/ h**参考文书：
https://en.wikipedia.org/wiki/PCI_Express

谢谢！

超級狗

PCI Express Basics and Background

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Quantum_

Dear Super
) o; f# P+ i; {' r6 d/ \+ ?, ~I still can't understand what happened to PCIe receiver signals to make them transmit signal from Device to Host, after reading your attachment carefully.
7 a4 U  [4 s! @8 J4 m  g1 kDo you mean that the answer of my question is concluded in the chapter below?
"Credit-based flow control is point-to-point based, not end-to-end, "
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7 `8 G. I. f# }  N  n. z, x"Split Transactions"

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" B) M6 R! e6 w; ~5 p3 s$ ?Do you have any other stuff for a rookie EE to learn about the PCIe Dispaly Card.
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Thanks very much.


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ykwym

PCIe的有些包发出来是需要接收端发信息回去，确保包是一定被收到的。so。。。

alexfu1984

就需要这个东东，好就一个字