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Comment by emilfihlman | Hacker News Reader

The sd card is the biggest weakness of all SBCs.

EMMC, wireless and some way to connect a camera (usb or CSI) would be perfect.

Yeah, I'd be happy with a board that's identical to the RPi3 but with eMMC rather than SD. Not only is SD less than reliable, it's slow.

The Raspberry Pi Compute Module 3 is just that, the SoC of the RPi3 with 1 GByte memory and 4 GByte eMMC on a SO-DIMM module. You need a baseboard though to plug it in. Either the Eval Board offered by the Foundation, or a Revolution Pi if you aim for industrial use, or some other baseboard.

I had no idea that the slot it used was literally just a SODIMM- I thought it was some other strange slot. That is really interesting.

This. I wonder how much it'd cost for them to just add a bit of on-board storage.

The now defunct CHIP computer costed 9$ and had on-board storage, so there you have a cap.

That used raw NAND flash, which is kind of nasty. I'm not sure they ever quite got it working right before they went under.

Raw NAND is highly preferable to SD or USB drives. You can at least have wear leveling in the OS/FS. SD/USB are bad because most have dumb controllers and just rewrite a page when it changes. Raw NAND is also consistent and meets datasheet specs, whereas SD you never know what you are getting.

What do you mean? I have two of them which work flawlessly...

Quick glance at Microchip shows, all in quantities of 5k units, $1.02-$2.28 per unit for 1Mb ROM, $0.36 for 1Mb flash, (if aiming for $1) $0.96-$1.10 per unit for 16Mb flash, and highest is 64Mbit at $1.95-$2.18 per unit. Memory is cheap if your product is popular or can share a big order with someone(s) else.

Since not a hardware guy, I don't know if PCB design or packaging cost goes up significantly for adding a 1Mb ROM or flash. I doubt it, though, given these kind of memory chips get used in dirt-cheap boards. Albeit with lower amounts of storage usually given those board try to minimize costs.

What do you do with 8MB when the OS is 512MB+? Adding NOR Flash is normally pretty simple -- No bad blocks and a standard SPI interfaces most embedded devices have controllers for. The high end controllers can typically map NOR flash directly into the system address space.

I was thinking it might be good for RTOS alternatives, a tiny Linux, or (relevant here) something to deal with SDcard problem. Tell users about it with suggested action.

And you said 8MB. I just named off a range at different price points to help answer parent's question. I dont know embedded enough to assess what's needed here. Thanks for tip about NOR flash.

Nowadays one can buy 128GB SSDs for 20€ + 10€ external case with USB 3.0. Having 8 or 16GB of internal storage shouldn't add more than 10€ to the overall price.

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