Pi2 Design Idiot-Proof Ready-To-Go RPi/AES Streamer

We are currently making some changes due to parts issues. In addition we are seeing long lead times on the CM4. One option is to go with a version that has no eMMC. This would mean adding an SD Card, which might be simpler for folks, especially in the beginning. But even that version is in tight supply. I can buy 60 with 4GB ram and WiFi now. Not sure when I’d be able to get more. Maybe it’s just a short term fix.

does this make it less Idiot-Proof? I would still provide a programmed card installed.

 

I can also get a larger quantity of 1GB with WiFi and 0 eMMC.

 

Why not? Just hide it in the chassis so people don't mess with it.

 

Hmm. I guess I just automatically assumed if there was an sd card it had to be accessible.

 

A lot of equipment makers do this and it works out well; easy programming and prevents users from corrupting the cards.

lot of time they are on CF cards, but those are not as common now a days.

 

I Think it should. I lost 2 sd cards to my Volumio rpi. It would be a shame if the card died and You couldn't replace it.

 

The likelihood would be rather low. Plus, a simple "take these screws out and replace the card with this one I just sent you" would probably suffice.

 

I know that high endurance SD cards (the type used in dash cams) are highly recommended for Octoprint servers. I would imagine any write-heavy computing application would greatly benefit from using these.

 

It’s not a wear problem, it’s an unclean shutdown can corrupt the file system on the microsd card one. I’m not sure how the original design would have dealt with that but I think it’s a good idea if you use a microsd card to make it easily accessible just in case. It’s not all bad — this has some appeal for diy hacker types who want to install a better, I mean different, distro, and that might help sell a few more units. Michael can make the officially supported image(s) available for download so users can flash a new version in case they run into a problem.

 

I have a power down circuit supported by a volumio plug in. This allows the OS to hold power after the user switches the power off. After a full shutdown the OS releases the power so no corruption.

Volumio made this plug in for our 503HTA tube hat and we just copied the circuit. Unfortunately, changing the OS will lose this ability. Powering off can then corrupt the sd card.

 

When JRiver first introduced a plug & play Pi SD card (ie. OS and JRiver pre-installed) it was annoying because it wasn't user updatable; if the card became corrupt for any reason you had to wait for a new one to be sent out from JRiver.
There are actually two separate issues here aren't there: whether the user can update/re-write the card, and for eMMC the issue would be the same/similar as an inaccessible SD card.
Secondly is whether a completely failed card can be replaced by the user.

 

Using volumio with the power circuit I mentioned before, we avoid both sd card and eMMC corruption. But with other OS’s it sounds like an externally accessible sd card has value. Then it’s up to the user to avoid powering off without a proper shutdown first.

And I suspect the non-eMMC compute modules will always be easier to get.

 

Where the Old El Paso girl when you need her, "why can't we have both?"

But seriously, the way that @coin777 said 'lost' suggested more than just a corrupt card that needed to be reflashed. And small Linux installs can do a lot of writes, which combined with cheap cards that have poor wear leveling can definitely kill them. But my experience is with Octoprint, so maybe it truly isn't an issue here.

Either way, I think we all agree that if it is an SD card based system, the ability to change cards is definitely preferable. And a stock image that can easily be etched is going to reduce support demands.

 

I just bought 60 CM4’s w4GB and WiFi for $50 ea. No eMMC so SD Card is definitely going in the final rev. We plan to use Samsung Extreme Pro cards.

As a side note, the 170 1GB boards I was looking to get were sold by the time I went to order them this morning.

 

From casually reading the relevant thread here one of the prerequisites for running the HQPlayer distro is 4GB of RAM so maybe a bit of a blessing in disguise for Mercury if that takes off?

 

Great stuff.

Sandisk, perhaps, rather than Samsung? Not specifically high endurance, but probably doesn't matter. I've used Sandisk Extreme for years and have never had a failure.

 

That was my other choice. I think they are about the same price.

 

Sorry, my point was you called them 'Samsung Extreme Pro', and I wasn't sure that there is such a thing. I know of Sandisk Extreme, and Samsung Evo.

 

Yeah, it’s Samsung Endurance Pro.

 

Ah, perfect, thanks for clarifying! I could have been a lot more clear in my post when i asked the question.

Those are exactly what I use in my Octopi and dashcam. Probably unecessary precaution, but reducing any failure point is always a good thing in my books.