New M.2 extender board pinouts reversed

Yup. You’re absolutely correct. The FPC cables cannot be interchanged, even though the board is flipped upside down. The contacts are facing the boards, but the cable still needs to be twisted, just as you said. You’re a pretty fart smeller (smart feller) aren’t you? I couldn’t see it without placing both cables side by side.

Anyway, I was lucky. eMMC took a hit, so I had to reload the image from SSD, but all appears to be working ok. Whew!!!:man_facepalming:

Dunno about smart but thank feck for that as hopefully there is only me buying new.

The previous conversations about the pins being reversed and the ribbon cables confused me much so I spent some time with the ribbon and boards thinking eh!?

My solution isn’t eloquent but it should work but anyone else if you are going to reverse the board you will reverse the pins and just have a different sided ribbon cable will not do that for you.

I am twisting 180 degrees so I can fit it over the heatsink, so pins are reversed so have got a same side 20mm and dunno how eventually it will look.

I got 40pin type A ? Think so from measuring

If your ribbon is 10cm, that’s pretty long. Isn’t it easier to let the SSD face the heatsink, having plenty of space in between?
Mine is only about 6mm away from the heatsink, now. But the dual fans blow directly in between them, so I’ll keep a close eye on the temp.

Haven’t got an ssd its a m.2 sata adapter, but yeah could right angle sata connectors would be a bonus, it me lovely fan that now causes a prob…

But if there was such a thing as one of these but the other connector was on the flip side it would be so cool as then you could have the choice. It would act as an extender/reverser for me opening up the sd reader access is actually a major thing, but we are all different and what would be a few $ would give that choice.

Or an alternative m.2 to 40pin fpc reverse mini board but prob the above would be cheaper.

Marvell do a range of 4 port with various RAID / Hybrid hardware configs or straight configs on 1 or 2 lanes.
They are just a bit pricey but great for NAS like the iocrest ones.

But you might even want to have more USB ports which is also a bit cheaper the assumption seems to be a single SSD.

Its Ok if you put up with the loop over the sd slot and guess a longer cable can make that much easier but also the heat distribution from the cpu cores is probably not designed to be upside down and really just confused to why that way was chosen, but hey :slight_smile:

I guess also there is this type of device where you might run face down and have a riser cable to a full size pcie device.

To be honest $59 for an m.2 sata is the going price as cheaper 4 port full size cards are horrid single lane port switching (FIS) affairs and the x2/x4 full size cards are about the same price as the m.2.
It would be interesting if Radxa can provide either full size or m.2 2/4 lane for any less as struggling to find alternatives.
To be honest I prefer the M.2 format and the relatively blank M.2 extender makes a great ‘prototype’ mount where quite neatly you can add a 5v Buck maybe even a fan controller.
You can take 5v from the GPIO but a separate buck is cheap and failsafe.

USB wise I noticed you can get these


And with

Fan wise I got one of these as without need of libs or software it will work from the go.

I really do love the form factor of the RockPi4 and it is a feat of engineering that they have managed to cram all that in and retain the Pi form factor .
The SD card I just find frustrating to have the SD so inaccessible with no SPI Nor and USB boot.
Its nothing major but Radxa could provide a extender/reverser @jack like the above it just means the form factor is far more flexible and for old dudes without the need for tweezers and angst it gives the choice on how to mount, prob much better than me twisting ribbon cables but you can.
You can get same polarity extenders already and maybe should be part of the kit if you wish to fit a Hat and extend that way and could maybe stop confusion over why 2 relatively short cables are provided.

Also the only other thing I noticed and that is the heatsink could do with some shim?
The rib around the cpu shape is also relatively pointless and makes it much easier to damage the other components that are extremely close in proximity.
The surface should just be flat and maybe more milled away than the component indent.
But even after a bit of a disaster with the first it has not decreased my enthusiasm.
Adding that modular aspect via PCIe makes an SBC have much wider appeal as it can be tailored to solution.
The RockPi4 is an amazing little board with some very clever thinking behind it.
Panfrost in 5.2 and really its what a Pi4 should be like but have a hunch it will be no where near.
Well done Radxa as its layout is exceptionally good.

Sorry for the delayed reply. But, looks like you didn’t need one, lol.
Been fighting with FreeCAD. Came here for a break.

Messed (more accurate for me than ‘worked’) with RockPi yesterday. Created another user account and joined it the adm group from the terminal command line. Also went into GUI app and made it a member of ‘root’, ‘sudo’, & ‘pulse’ groups.
But, when I logged in under that account, it wouldn’t allow me to ‘sudo su’, saying that the account wasn’t a member of the ‘sudo’ list, so it was going to report it. Don’t think the GUI works. Wanted to install sysbench.

Anyway, I managed to add ‘temp’ and ‘CPU usage’ meters to the system tray.

Spent a lot of time playing YouTube videos and the temp only rose from 35 deg to 36 deg. So, I think the dual RPi fans are doing their job pretty well, but they’re a bit noisy. Thought about running them from a 3.3v GPIO instead of 5v pin, but not sure about pulling too much current with them being in parallel. Need to do the math.
That reminds me, I don’t think anyone answered your question about how many pins there are on the FPC ribbon. I count 40. But, you probably figured that out by now.

My eyes and fingers couldn’t count it, I measured it at 20mm and its .5mm pitch so yeah went for the same.
I went for one of these.


I don’t want to be wiring to the gpio as will leave that open for further expansion and also I can keep totally off the boards regulators and be practically failsafe via my 12v supply.

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Excellent solution, especially when using a 12v psu! Gotta admit, the RPi fans running off the GPIO header is a little Mickey Mouse, by comparison.
Thanks for the pointer. So many goodies to research.:money_mouth_face:

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