Questions tagged [pcie]
PCIe or PCI Express is a high-speed serial computer bus that offers higher speeds and a lower pin count than earlier standards such as PCI that it is designed to replace. Questions should relate to PCIe design issues not general consumer PC / peripheral issues.
298
questions
44
votes
5
answers
71k
views
Does PCIe hotplug actually work in practice?
I've got into a discussion in the comments of https://security.stackexchange.com/questions/109199/is-physical-security-less-important-now-for-securing-a-server?noredirect=1#comment194327_109199
The ...
- 46.9k
26
votes
1
answer
26k
views
Address Spaces in PCIe
There are four address spaces in PCI express:
Memory Mapped
I/O mapped
Configuration Space
Message
Can anyone please explain significance of each address space, and it's purpose in brief ?
As per ...
- 361
21
votes
1
answer
4k
views
Why is there a little nose on the PCIe connector?
PCI express cards have an edge connector with a little notch in it to prevent the card from moving if the socket is longer than the connector. Additionally, the printed circuit board has a protrusion ...
- 500
21
votes
1
answer
5k
views
PCIe, diagnosing and improving an eye diagram
I have implemented a design that uses PCIe. It is somewhat different in that the PCIe interface is used as a chip-to-chip communication lane on a single PCB (e.g. no PCIe connector).
The root ...
- 301
21
votes
2
answers
74k
views
What are "sense" pins in 8-pin PCI Express power plug?
I have an ATX PSU that has two 6pin connectors for PCI Express power. Both have Gnd on the lock bar side, and +12V on the opposite side. I lost modular cables that came with the PSU, and it made me to ...
- 689
18
votes
1
answer
3k
views
Why are PCIE's coupling capacitors so large
I was looking at the PCIE specification, and I don't understand the
requirement for coupling capacitors. For 2.5GT/s, the standard requires
AC coupling capacitors of 75nF to 265nF. I tried to ...
- 388
17
votes
4
answers
5k
views
Are PCIe and USB 3.0 the same interface?
I know the title may sound provocative, but I was looking for a PCI hub, and found solutions like these:
I noticed that on the PCIe side, there is actually only one adapter (which looks passive) with ...
- 828
15
votes
3
answers
38k
views
What do the different interrupts in PCIe do? I referring to MSI, MSI-X and INTx
We have the following interrupts: MSI, MSI-X and INTx. What do these different type of interrupts do in PCIe? I only need a short description. I only know that in PCIe interrupts are generated as ...
- 12k
15
votes
1
answer
2k
views
Termination of unused mini PCIE lines on a USB only device
We're designing a USB only mini PCIE card and I'm trying to work out if it is required, or at least good practice, to terminate the high speed lines that are unused on the mini PCIE card. I can't find ...
- 188
14
votes
3
answers
7k
views
Is USB-C a technically viable substitute for SATA Express connectors?
SATA Express, the successor to SATA, is too new to be widely used yet, but the advancing speed of SSDs appears to make it inevitable, the same as SATA replaced parallel IDE. Despite the name, it isn't ...
- 317
11
votes
3
answers
8k
views
What is the difference between full duplex and dual simplex?
What is the difference between full duplex and dual simplex? I can not really distinguish the difference. Is it the fact that in full duplex, data can be exchanged simultaneously in both channels ...
- 213
10
votes
3
answers
13k
views
What does the "posted" mean in posted PCIE transaction?
What is the etymology of the word "posted" in "posted PCIE transaction"? I've worked with PCIE and I understand the difference between "posted" and "non-posted" PCIE transactions, but I don't ...
- 569
10
votes
1
answer
7k
views
Is it possible to only utilise SMBus on PCI Express 1X?
According to the Wikipedia page on PCI Express, the PCI-e 1X slots have 18 pin positions on two lanes (so 36 pins) and positions 5-9 represent SMBus and JTAG.
I'd like to hook up a µC as an ...
- 10.8k
9
votes
1
answer
29k
views
WiFi module says "mini PCI-e format" with "USB host interface" - what does this mean?
The specifications of a WiFi module meant for embedded projects, says --
mini PCIe format
Host interface supports USB.2.0
Works with any board with mini PCIe.
Not sure about the interplay of mini ...
- 3,534
8
votes
2
answers
9k
views
What does "configuration" refer to in PCI and PCIe? How is this different from "Enumeration"
I am not being able to find a clear description of what configuration means in PCI and PCIe. I have found something called as configuration space, but without knowing what configuration means, it is ...
- 12k