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privatelypublic | 5 months ago

Are they actually extra? Or does the other cable simply route them over coax? Answer here is to grab a couple SFF-???? Breakout boards, a scope, and a signal generator.

Another thing to consider is isolating all but the first PCIe lane.

discuss

order

geerlingguy|5 months ago

> Answer here is to grab a couple SFF-???? Breakout boards, a scope, and a signal generator.

Yeah, I've considered buying an extra adapter and just probing pins — I don't have a spare M.2 to OCuLink adapter but will probably order a few different models to see if there are any differences there too.

> Another thing to consider is isolating all but the first PCIe lane.

The Pi nicely does that for me ;)

privatelypublic|5 months ago

Haha, touché- forgot the Pi5 only has a single lane.

The comment came out of knowing if the cable's a little dodgy the timing could be off- scrambling the PCIe signals (easier to just tape it off than look up if its supposed to matter and then tape it off anyway), and the fact my first HBA had the "QC pass" sticker prevent some lanes from connecting and the whole card was unresponsive as a result.