Flexible PCI extender?

[pstnotpd]

I know I've asked this before, but has anybody found a flexible PCI extender cable so that slicekit coreboards can be stacked?

[mon2]

Have a look at the various vendors that offer x1 lane PCIe extender cables on aliexpress.com.

Search for "pcie 1x extension cable" and numerous (Chinese) vendors will pop-up. Have not personally tried them (yet) but they should be fine for your consideration.

If you are in a rush and in the US, consider:

http://www.adexelec.com/pciexp.htm

We have used their services in the past with positive feedback.

As a general rule, keep the length of the cables to a min to avoid issues related to high speed data transfers. Hope this helps.

Kumar

[pstnotpd]

Search for "pcie 1x extension cable" and numerous (Chinese) vendors will pop-up. Have not personally tried them (yet) but they should be fine for your consideration.

Yes, I've seen loads of those as well.

However, if I look carefully at the pictures I can see that lanes are usually combined on the PCB part. As I understand it the lanes should remain separate to get a proper connection for the slicekit.

Ah well, maybe if I can find the proper parts I'll try to cobble one up. Unfortunately my hardware skillz leave much to be desired....

[mon2]

Ahh...very astute observation on your part. Some of the zoomed up photos do indeed reveal that some of the PCIe pins convert to grouped traces which is definitely not desirable for XMOS slice kit interfacing. While the referenced extension cables are fine for the true PCIe interface, they will not be for the XMOS designs. Technically, for an extension cable, the vendor should have extended the signals 1:1 and not assume they are for PCIe bus use. Unless someone offers such a solution, a custom design would have to be created. Let us review this in detail as we have a long history of PCIe designs and have the tooling in place. Perhaps an idea is to have a male PCIe PCB to 2 x 20 pin IDC header -> mate with a ribbon cable of your choice -> convert the ribbon cable back to a PCIe female socket with a true 1:1 pin mapping. However, then the concern is what pitch should be used for the ribbon cable and IDC headers. If you consider a standard 0.1" spacing (like the older IDE hard drive cables; commonly available) - the cable and connectors will be too wide and will interfere with other XMOS expansion ports on the main board. Could use smaller pitch parts, say 2 mm or 1.27 mm (http://www.donconnex.com.tw) but then sourcing such cables may prove to be difficult.

[pstnotpd]

As an out-of-the-box extender seems unavailable I'm thinking along the lines of a PCB plug. That way the coreboards can be fixed in position and the actual connections are as short as possible. The only (minor?) problem would be the "twist" in the traces.

Obviously I don't know much about component availability but I'm pretty sure this should be feasible.

[Chendy]

Did anybody find a cable that works?