5 ms·
A NVMe compatible M.2 M Key connector (like the Rock 5 Model B [0] has) would have been really nice. I'm starting to accumulate old but good, yet small in stora
by qwertox 3y ago
A NVMe compatible M.2 M Key connector (like the Rock 5 Model B [0] has) would have been really nice. I'm starting to accumulate old but good, yet small in storage space terms NVMe's which I'm no longer needing, but which would be perfect for a Raspi. Even if the PCIe bus were an older generation and not as performant as the NVMe.
The microSD card slot is really great to have, to get up-and-running, but once it's clear which function the board will serve, being able to move over to a directly connected old NVMe would really be a benefit, also in terms of reliability. These microSD cards scare me, yet I make full use of them.
Finally having a battery backed RTC on it is really great news.
[0] https://wiki.radxa.com/Rock5/hardware/5b https://wiki.radxa.com/Rock5/hardware/5b
- teamonkey 3y agoThe blog post says they're releasing a M.2 hat in "early 2024"
- mintplant 3y agoI don't love that you'll have to choose between PoE, M.2, or active cooling / a case.
- danbee 3y agoYou won't have to. They can all be stacked.
- SparkyMcUnicorn 3y agoWould active cooling work underneath another hat?
- mbreese 3y agoIt looks like the M2 socket will be connected with a flexible ribbon, so it is possible that it could be mounted below.
- bpye 3y agoAlso looks like PCIe is exposed via an FPC connector. You could probably come up with a scheme to have an M2 device mounted behind the board - if you really wanted. Only having a single lane of PCIe 2.0 is a little unfortunate. I wonder if the inevitable compute module will get more or not. It seems that their IO chip is also attached via PCIe but it provides a lot of the interfaces that you’d expect to have - so my hunch is that it’ll be included on any CM5.
- rasz 3y agoit can be forces into "experimental" 3.0 mode so thats something.
- arwhatever 3y agoThen surely there must be competition or a record for “tallest ever,” hopefully requiring each layer to be functional.
- extraduder_ire 3y agoI think you can have over a hundred different i2c devices connected to the same bus, so it'd get pretty tall if you can power them all. 10-bit i2c (not very common) can do almost a thousand. Although, you'd need specific rules if you wanted to prevent someone just layering up always-on LED boards.
- dmitrygr 3y ago> you can have over a hundred different i2c devices connected to the same bus In theory sure, in a world with zero-inductance zero-capacitance busses and infinite-sink-current drivers. In our reality, however, you'll start having issues and start requiring stronger pullups and lower speeds long before you get to a hundred.
- dfox 3y agoOne pretty popular home alarm brand uses I2C as “the bus” with somewhat ridiculously large cable lengths for what was designed as a board/enclosure level cheap serial bus. It is in no way a sane design, but it seems to work.
- dmitrygr 3y agomaybe at a 100Hz clock rate?
- monocasa 3y agoThis reminds me of one of the dirtiest things I've seen in this space. Saw i2c buses bridged across multiple chassis by bridging the boards with CAN transceivers. It mostly worked, but I feel like everyone who signed off on that design review should feel bad about the atrocity they created.
- CTDOCodebases 3y agoYou don’t have to as long as whatever devices manufactured have a PLX on them. This adds to the cost though.
- sillysaurusx 3y agoFwiw I bought a sleeve for my M.2 SSD and it plugs into usb3 with very little slowdown. It gets 500MiB read and 1.2GiB write. Haven’t measured vs native M.2 to compare, but it’s fast enough that I’d be surprised if the pi were blocked waiting for I/O vs native M.2. And native M.2 comes with increased manufacturing complexity.
- LtdJorge 3y agoAre you sure it's 1.2GiB? The RPi comes with 5Gb/s USB ports, which is 596MiB/s Now that I think about it, Linux may be caching writes, but even then double the write speed compared to the read speed seems weird.
- deleted 3y ago[deleted]
- sillysaurusx 3y agoOh, I didn’t test on a pi, just a mac. And yeah the double write speed was super weird. Thanks for answering my internal question about why ~500MiB seemed to be the max.
- heresie-dabord 3y agoI recommend booting Pi 4 and Pi 400 from external (USB) NVMe in an enclosure.
- antx 3y agoIndeed, but it's somewhat of a hassle. Having everything integrated on the board, or in the same case, is nicer.
- HankB99 3y agoYIL a Pi 4B can run from a directly connected USB/NVME SSD. I've been using USB/SATA SSDs and all I have tried require a powered hub. Do note that I don't just just boot it up and proclaim "It boots - ship it"[1] I thrash it with various disk benchmarks and stress tests to be absolutely certain the SSD does not disconnect due to insufficient power. [1] I suppose this is the H/W equivalent of the S/W engineer's proclamation "It compiles - ship it!" And I guess this dates me since S/W is pushed rather than shipped these days.
- proxysna 3y agoSame with orange pi5 and 5b. Having an option for a faster and reliable storage is amazing. SD cards are great when you prototype or need just enough storage to netboot a device, but past that it is limiting.
- schappim 3y agoThis would limit you to just connect SSDs. Their solution opens up more versatile access to other PCIe devices.
- ltbarcly3 3y agoIt would not limit you to just SSDs, the m.2 connector on the rk3588 devices generally exposes 4 pcie lanes and an adapter to make this a full pcie slot is already available. So really an m.2 nvme connector is the best of both, you can turn it into any other pcie connector you want via an adapter, but you can just put an nvme ssd directly on the board without a hat.
- 15155 3y agoThe best part about M.2 E key is that it does not require +12V.
- mastax 3y agoIn addition to the ability to adapt M.2 slots into PCIe via an inexpensive adapter, there is a growing ecosystem of M.2 cards for most of the things you'd use a PCIe card for. USB controllers, SATA controllers, Ethernet controllers, FPGAs, even display adapters.
- gerdesj 3y agoYou can get some rather large USB sticks these days. Amazon is awash with 928Gb units for about £10 which are probably not the best. A 256GB or 512GB from a known brand is around £30-50. There are several USB ports on a Pi and you can always boot off a SD card. Finally, if a network is available then network boot and use NFS or whatever. The RTC is a cool addition and long overdue. At work I have three Pi 3s with GPS hats and aerials acting as stratum 1 ntp servers. The hats have a RTC included which is handy after a reboot. My use case is "reasonably accurate and stable time" so sub milli second is good enough, I'm not too fussed about nano seconds! I want logs to correlate and desktop clocks to be reliable.
- gorgoiler 3y agoFlash storage like USB sticks is a crude comparison to an SSD or NVMe with cache and a controller capable of parallel operations. A USB flash drive is like a dumpster. Big bandwidth when the lid is open but it’s got poor performance for fetching and storing lots of things all the time. An SSD or NVMe is more like a rolling auto tool chest. Same big metal box, but much more performant for complex and numerous read and write loads. Or to use a computer analogy: SSD is like a hard disk, USB flash is like a tape drive.
- Fnoord 3y agoOr use USBv3 to NVMe enclosure. Cheap and good ones can be found on Ali.
- abrugsch 3y agoGet the caseless ones and then 3D print my enclosure ;) https://www.printables.com/model/590143-case-for-usb-to-m2-nvme-ssd-adapter https://www.printables.com/model/590143-case-for-usb-to-m2-n...
- GOONIMMUNE 3y agoFYI I believe all of those ~1TB $10-20 USB drives on amazon are scams- basically set up to trick your computer into showing a terabyte of disk space available, but not actually having that much available if you try to write it all. I was in the market for "largest reasonably priced usb drive" earlier this year and ended up with a 1 TB usb drive for about $80.
- Fnoord 3y agoOn a CM5, a lite or one with eMMC would suffice in combination with NVMe. I have CM4 with eMMC and use SATA w/them.
- birdyrooster 3y agoMeanwhile in reality when nvme drives die in like 6 months… ughhhh
- RussianCow 3y agoSorry, can you elaborate? Is the death rate of NVMe drives known to be significantly faster than that of other types of drives? I hadn't heard of this.
- MrDrMcCoy 3y agoI can only speak from my own experience, but there are a number of low to mid grade SSDs that use truly awful flash and/or controllers. I've bought many of them over the years for unimportant workloads, and have been unpleasantly surprised by how quickly I can burn them out. It's really worth it to shell out for higher end models just for the increase in durability.
- RussianCow 3y agoYeah, I'm not doubting that, and this is consistent with my own experience. But the claim was that it was specific to NVMe SSDs, which I find very odd.
- ciwolsey 3y agoOut of curiosity which brands?
- MrDrMcCoy 3y agoAll but the highest models of SanDisk have done this to me, as well as the lowest end of Western Digital, ADATA, Kingston. Same for some lesser brands that I've forgotten (not fakes, just shoddy).
- ur-whale 3y ago> A NVMe compatible M.2 M Key connector Yeah. The Lichee Pi 4A has one of those under the board, it's really useful. I wouldn't even blink if they completely jettisoned the MicroSD slot, these have proven to be a giant PITA over the years (slow, unreliable, etc...) I really don't understand why they would miss that.
- comboy 3y agoMicroSD allows for a really low cost deployment (availability issues aside), especially when PXE is not suitable.
- sitkack 3y agoFor the low cost route, boot off USB flash drive.
- ur-whale 3y agoGood luck doing "deployments" on SD drives and still have it run 6 months later, especially in environmentally unfriendly environments. Theses horrible little things die all the time, even when you buy supposedly high quality ones.
- HankB99 3y agoThe CM4 exposes a PCIe 1.0 x1 (Not sure about the revision) lane and can boot from an NVME SSD. It will be nice to have this capability on the Pi 5 with all of the other connectors (except for audio.)