03-16-2021, 05:11 PM
(This post was last modified: 03-16-2021, 05:20 PM by dsimic.
Edit Reason: Clarified a bit
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(03-16-2021, 04:42 PM)barray Wrote: Well, if people are asking the same question over and over, it seems like it's a good time to invest some time to automate the handling of such queries. I think they now have a Telegram chat or something that advises when products are about to drop, but I guess they really need something else too.
That's all fine, but I'm still hearing nothing from Pine64, and I haven't asked about product availability.
(03-16-2021, 04:42 PM)barray Wrote: Well I was initially looking at using NAND SPI flash with quad SPI: https://nz.mouser.com/datasheet/2/949/w2...608377.pdf
That gives you up to 50MB/s and you could then pick up some extra speed with the RAID format. I suspect the latency between read request and reply to be constant for example (and most of these devices support artificial delay in the worst case), so you would just need to be smart about chip select and could multiplex whilst each chip is busy. If you were doing mirroring for example, I wonder if you could even chip select two identical flash units at the same time.
That would be really neat!
For a USB 2.0 storage device, using quad-SPI flash should provide more than enough speed, and would allow rather easy implementation of different RAID levels, while keeping the price of device low. Is there enough documentation available for the BL602?What about the USB interface, required for exposing the storage to the host? I cannot see that available in the BL602?
(03-16-2021, 04:42 PM)barray Wrote: I would try to stay away from this, I imagine this will just end up being a headache in the long run. There's no reason why a flash drive company might not run several revisions based on what parts are cheapest at the time, so components may not even match up even if we buy the same device.
On second thought, I agree with you. There's no way to know in advance what's actually inside an off-the-shelf USB flash drive, regardless of the actual make and model, which invalidates the whole idea about "harvesting" the parts.
(03-16-2021, 04:42 PM)barray Wrote: Right, and it's the project that most people point towards when you suggest 'open source storage'. This is why I think this project is so important - because there really isn't anything out there being actively worked on.
Furthermore, no open storage device is easily and inexpensively available to pretty much anyone, which is the key, if you agree. I wonder where and how could I buy one of the referenced OpenSSD development boards? Even if buying those boards is actually possible, it would surely cost an arm and a leg, effectively rendering them unavailable.
