Which cheap quad core ARM? (A53 or similar, 64 bit), MIPI DSI - Page 1
Forum section: electronics / general

author: loki42
author_rank: Frequent Contributor
timestamp: February 08, 2019, 02:15:21 am
content: I'm looking for a quad core ARM chip (A53 or similar, best floating point performance possible for the $), needs I2S with TDM, MIPI DSI or parallel RGB LCD support and a linux supported OpenGL ES GPU for running QT.Cost is the main factor and board size doesn't matter too much.Low power consumption a bonus. Modules / SOM with RAM a bonus if cheap / easy(must be <35 USD in 250 units including RAM / PMU). I've looked at the allwinner A64 chips, especially the SOPINE but i'm interested to see if other options makes sense. My volumes are small (1000 / year) so I suspect some manufactures won't be keen. The Olimex boards look interesting. I'm wondering if there is a Rockchip / samsung (Nexell S5P6818), Amlogic / Qualcomm (heard these are hard to get) something else chip i should be looking at? I'd love to use the Pi compute module but the I2S doesn't support TDM.Obviously NXP/TI/etc are too expensive for my requirements.

author: Marco
author_rank: Super Contributor
timestamp: February 08, 2019, 03:44:21 am
content: NanoPi Neo Core/Air/Duo2? Not as cheap as they used to be, but then they don't have any real competition.

author: loki42
author_rank: Frequent Contributor
timestamp: February 08, 2019, 06:11:03 am
content: The nanopi stuff looks super cheap but hard to embed as the don't expose LCD support on the boards you mention. I need either MIPI or parallel LCD, if possible 24 bit.

author: nsrmagazin
author_rank: Regular Contributor
timestamp: February 08, 2019, 08:25:36 am
content: I love it when I see requirements like this, its just like a company manager, I want it best but for the shortest time, you have to do both! If you want good it will cost more, if you want it to be cheap it will not be good. Which one do you want?You can try this:https://eu.mouser.com/Semiconductors/Embedded-Processors-Controllers/Microcontrollers-MCU/ARM-Microcontrollers-MCU/ARM-Cortex-M4-Core/_/N-a85pc?P=1yztkjiZ1z0w8ejor this:https://www.tme.eu/en/katalog/#id_category=100636&search=arm+quad+core&page=1&s_field=accuracy&s_order=DESC

author: Marco
author_rank: Super Contributor
timestamp: February 08, 2019, 09:01:56 am
content: To be fair, SOPINE and Pi compute have really taken the bottom out of the SOM market ... and opened up new applications in the process for which a "proper" SOM or custom board simply isn't on the cards.

author: brucehoult
author_rank: Super Contributor
timestamp: February 08, 2019, 09:10:44 am
content: Quote from: nsrmagazin on February 08, 2019, 08:25:36 amNot only that, but says he wants a chip, and then talks about boards!

author: brucehoult
author_rank: Super Contributor
timestamp: February 08, 2019, 09:11:19 am
content: Do you want 32 bit or 64 bit or don't care?

author: loki42
author_rank: Frequent Contributor
timestamp: February 08, 2019, 04:04:36 pm
content: 64 bit if possible, there are some nice QT performance improvements that are only on that arch.SOM or chip, I forgot to say which core but a53 or similar, quad or more only. Open source GPU support would be great, such as the Qualcomm Adreno. I'm running wayland / EGL not x.

author: loki42
author_rank: Frequent Contributor
timestamp: February 08, 2019, 04:09:50 pm
content: Cheap is the priority, MIPI DSI/LCD, quad core, A53 or similar, working opengl es under recent Linux kernel, mainline a huge bonus.

author: krho
author_rank: Regular Contributor
timestamp: February 08, 2019, 05:58:03 pm
content: Well if you find any I'd be surprised. AS this is the thing we are also looking for but unable to find.Which on the other hand is surprising as you can get really good smartphone for something like 150€

author: loki42
author_rank: Frequent Contributor
timestamp: February 08, 2019, 06:02:51 pm
content: Quote from: krho on February 08, 2019, 05:58:03 pmDid you evaluate the Nexell or Allwinner A64 / H series parts? Seems to be plenty of options in the lower price points. I'd love something stocked by LCSC or a major distributor but it seems like buying from Aliexpress / etc the only way. I'm already using a part that's working well but I'm keen on a bit more CPU performance, thus the move to a quad chip.

author: krho
author_rank: Regular Contributor
timestamp: February 08, 2019, 07:54:05 pm
content: We haven't evaluated that.. The problem we have is that we'd need at least 5year availability. The QTY per year is a bit higher than yours ~2000pcs

author: nctnico
author_rank: Super Contributor
timestamp: February 08, 2019, 08:02:44 pm
content: Quote from: loki42 on February 08, 2019, 02:15:21 amAt such a low volume your R&D costs make the price of the chip not matter at all. You'll need to spend a couple of hundred hours at least to iron out the bugs on a device from NXP or TI. Count on doubling that by going for a more obscure manufacturer. Say at $80 per hour your labour costs to pay for 300 hours extra to get the obscure chip up &running would be $24 per board. Don't think a Linux kernel / BSP from a manufacturer website is ready to be used in a product. They are not! Tweaking and bug fixing will be required.However for 1000 pieces a SOM (system on module) won't make sense at all. It will be cheaper to do a full-custom design.

author: legacy
author_rank: Super Contributor
timestamp: February 08, 2019, 08:41:36 pm
content: Quote from: nctnico on February 08, 2019, 08:02:44 pmYup! And it also happens with WindRiver stuff. We did the mistake, which cost something like 900 euro for the fix, just to have the SMP working. The same happened with Linux, but it was more expensive.

author: PCB.Wiz
author_rank: Super Contributor
timestamp: February 08, 2019, 10:21:08 pm
content: Quote from: loki42 on February 08, 2019, 02:15:21 amMaybe an alternative is to look at what's needed to have the Pi compute module support TDM ?How many channels do you need at what speed ?

author: loki42
author_rank: Frequent Contributor
timestamp: February 09, 2019, 03:21:15 am
content: Quote from: PCB.Wiz on February 08, 2019, 10:21:08 pm8 in / out at 48 khz. Though the Allwinner stuff works well so I'm mostly looking into alternatives to that that might be cheaper / better (at the price point of really cheap) I'm selling a boutique consumer product but it doesn't have a ton of margin (yes I know) and my time is surprisingly cheap...I've found the mainline support of Allwinner gear to be quite good, though I don't know anything about the Octa core Nexell stuff, it is very cheap per flop.

author: OwO
author_rank: Super Contributor
timestamp: February 09, 2019, 03:54:35 am
content: Quote from: nctnico on February 08, 2019, 08:02:44 pmThe problem with that kind of accounting is that you aren't looking at long term costs, since 250 units of sales now might become 1000 units 2 years later. You also need to look at the big picture of what you end up with after the project: if you put the effort into getting a proper low-cost solution working, you end up with a valuable design with a value-add of the cost difference per unit. You need to think of it as an investment: if 250 units only breaks even (between the added labor cost and the saved BOM cost), and 250 units is the per-year sales figure, that represents a break-even time of just 1 year! After that you have ($100 minus $35) per unit of added pure profit.There is also nothing obscure about Allwinner, they are one of the biggest SoC manufacturer in the low end tablet market and almost every SBC worth your time uses either Allwinner or Rockchip.In addition, results from working out a low-cost SoC solution doesn't just affect one project; the design (and surrounding software work) can be reused in future projects. Reducing the price can also mean more sales. You can already buy fairly usable tablets for <$100, so why would I ever buy a product whose main feature is a low end SoC and costs $200? What about in a year when your competitor comes out with the same product but with a price lower than your BOM cost?

author: loki42
author_rank: Frequent Contributor
timestamp: February 09, 2019, 08:13:06 am
content: also from my original post: "I'm wondering if there is a Rockchip / samsung (Nexell S5P6818), Amlogic / Qualcomm" vs the allwinner. No expensive non mobile / tablet chips wanted. Has anyone used the other brands I mentioned in comparison to allwinner?

author: nctnico
author_rank: Super Contributor
timestamp: February 09, 2019, 11:33:38 pm
content: Quote from: OwO on February 09, 2019, 03:54:35 amBut you have to spend extra time on debugging stuff and can not spend that time on adding features and proper testing. I've used various SoC chips in the past and if you are not careful you can spend a massive amount of time to get something to work. In general: the cheaper the parts the bigger the black hole which sucks in your time.Another concern with the mobile device SoCs is longer term availability. With a SoCs from NXP or TI you can deliver the same product for at least 10 years if you want. This means that you don't need to put any effort in re-designing a product every few years and thus can have much more profit. All in all I think you first have to work out if you really need (or want) to compete on price instead of features. Component costs are a tricky thing to get trapped into. I've seen it before: cutting component costs leading to a device being obsolete by the time it hits the market. OTOH others went for an ARM chip from TI and can still sell a product which meets today's demands 7 years after it was designed.QuoteBut how bug-free (stable) are those devices? And what features do they have which actually work? And how do customers respond to that? IIRC my wife got a few of those cheap tablets in the past but they where all crap in some way.

author: loki42
author_rank: Frequent Contributor
timestamp: February 10, 2019, 12:02:52 am
content: To clarify:I'm deciding betweenRockchip / Samsung (Nexell S5P6818), Amlogic / Qualcomm / Allwinner / MediaTek. No TI / NXP / AD / Microchip etc unless there's a chip I've missed. I've you've got experience with any chip made by Rockchip / Samsung (Nexell S5P6818), Amlogic / Qualcomm / Allwinner / MediaTek I'd love to hear about it.

author: nsrmagazin
author_rank: Regular Contributor
timestamp: February 10, 2019, 01:24:00 pm
content: I am using media tek 6580 on my phone, I can say its better than Asus Prime ZF201.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: February 12, 2019, 03:27:54 pm
content: Quote from: brucehoult on February 08, 2019, 09:10:44 amWith Olimex you can have Both.Olimex sells a bunch of loose Alwinner Chips and the complete schematics and PCB designs for a lot of their boards are on github, which will give you a headstart when designing your own custom board around it.

author: MT
author_rank: Super Contributor
timestamp: February 12, 2019, 04:48:16 pm
content: Quote from: Doctorandus_P on February 12, 2019, 03:27:54 pmBut haven't it been established previously that Allwinner dont give away complete datasheets?! How is loki42 (or anyone else) supposed to be able to access I2S TDM from Linux without having access to the TDM interface specs to construct a Linux driver for it in the first place?

author: nctnico
author_rank: Super Contributor
timestamp: February 12, 2019, 05:43:08 pm
content: Having no datasheets and (also very important) errata sheets would be a red flag for me. It means you are totally unable to fix a problem yourself and thus not able to serve customers properly.

author: loki42
author_rank: Frequent Contributor
timestamp: February 12, 2019, 08:33:31 pm
content: The allwinner data sheets look pretty decent and are easy to find for the A64. GPU is in main line too.

author: loki42
author_rank: Frequent Contributor
timestamp: February 12, 2019, 09:56:03 pm
content: Yeah, and it's great they have a KiCad layout for the A64. They also have Rockchip RK3188 based SOMs as well. I'm not sure how the RK3188 and the A64 compare in performance / features though.

author: nctnico
author_rank: Super Contributor
timestamp: February 12, 2019, 10:08:55 pm
content: Quote from: loki42 on February 12, 2019, 08:33:31 pmBe sure to find the errata sheets as well. Every SoC has bugs and you'll need to at least go through them to check if they can affect your application. Usually 95% is benign and easy to work around but there can be some show stoppers hidden between them.

author: MT
author_rank: Super Contributor
timestamp: February 13, 2019, 12:28:47 am
content: Mmmkay! So datasheets seams available now days! Downloaded the A64 datasheet and manual and it looks at first glance reasonable decent yet a bit old 2015 and no erratas. Still bare metal coding seams to be pain in rear end, all Linux OS coding, and zero chip dev support from Allwinner.

author: loki42
author_rank: Frequent Contributor
timestamp: February 13, 2019, 12:31:31 am
content: I think it's down to Rockchip vs Allwinner for me. Rockchip seems to be more friendly to the Linux community. Others seem a bit to difficult to find info about.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: February 15, 2019, 01:02:15 am
content: I never looked too deep into these small linux boards (though I have a Cubieboard in use and some mostly unused Beaglebone's)From what I know the sellers of those boards are usually capable of delivering a working Linux distro with the hardware they sell.Having a quick peek at the loose IC's from Olimex:https://www.olimex.com/Products/Components/IC/It does not seem to be very usefull to use older chips than the A64 unless they need significantly less hardware to support them.Have you considered one of the Odroid boards from Hardkernel?They also hav AMlogic and Samsung Exynos and others, but some are above your budget.If you want the soure for the graphics engine ... good luck with that.If you're in for an adventure, just maybe it's worth to look into the new Risc-V stuff. It seems that samples are becoming available and it seems that it's mostly sold out because everybody is jumping on it.

author: brucehoult
author_rank: Super Contributor
timestamp: February 15, 2019, 02:32:32 am
content: Quote from: Doctorandus_P on February 15, 2019, 01:02:15 amThe Odroid boards are mighty if you want processing power. The XU4/XU3 have the same SoC as the international version of the Galaxy S5 are only about 2.5 times slower than an Ivy Bridge i7-3770. The XU4 is only 32 bit, but is 1.7x faster than the 64 bit C2. The C2 is 1.55x faster (on my tests) than a Pi 3 which is also quad-A53s. And Hardkernel supply a 64 bit Linux for the C2, whereas the official OSes for the Pi 3 only use its 32-bit compatibility mode.So the overall difference between a Pi 3 and i7-3770 is just over a factor of 6. Oh, and I make the Pi 3 1.6x faster than the Pi 2 on my usual test, for almost exactly 10x slower than the old i7. New top end i7s are 2x faster than the 3770.QuoteI think almost everyone is still just making Multi-Project Wafers (aka shuttle runs) in which you only have to pay the costs of a small fraction of the mask, but you only get 100 chips from each mask so the setup costs are relatively small ($30k maybe) but the individual chips are very expensive.I expect multiple companies will be moving to volume production on various devices this year.

author: loki42
author_rank: Frequent Contributor
timestamp: February 15, 2019, 03:40:41 am
content: The Exynos chips look good but I'm looking for a SOM if possible, not a single board computer, as none of the Odroid stuff seems to have a MIPI-DSI or parallel LCD output, which I need.I'd like eMMC and no additional ports in a SODIMM or solder down form factor if possible.These H6 boards:https://item.taobao.com/item.htm?spm=2013.1.20141002.5.46cd2b99xe2aKq&scm=1007.10009.70205.100200300000001&id=569157333974&pvid=667c7a94-e486-4e30-adbc-584aaca3365fOr the SOPINE still look good. I've found a few good Rockchip boards but most don't have TDM / multichannel I2S. Amlogic S905 has support for that but I can't find a cheap SOM, though the chips are cheap.

author: loki42
author_rank: Frequent Contributor
timestamp: February 15, 2019, 05:07:49 am
content: A53 or similar 64 bit ARM. Sorry it should say that in the title.I gave a list of requirements at the start but most important are MIPI-DSI with working OpenGL ES and I2S TDM / more than 2 channel in / out.

author: JPortici
author_rank: Super Contributor
timestamp: February 15, 2019, 08:30:59 am
content: Next week on the 20th ST is releasing a chip that appears to be an ARM A-Something, capable of running linux. No idea on peripherals or pricing but it may be worth to wait?

author: MT
author_rank: Super Contributor
timestamp: February 15, 2019, 02:14:21 pm
content: Quote from: loki42 on February 15, 2019, 03:40:41 amHow do you know if the linux distro you chose have drivers for multi ch TDM and the distro that do have supports the board you want to use? It seams like endless chase to figuring out since Linux distros seams based on code blob tech!(i know nutthing about linux, im to old)

author: krho
author_rank: Regular Contributor
timestamp: February 15, 2019, 06:53:30 pm
content: Quote from: JPortici on February 15, 2019, 08:30:59 amIt's not going to be next week but on embedded world so in 10days or so. It's going to be something like IMX7Dual core A7 + m4. That's all they told us last week on "hands on" seminar for one of their other chips.

author: rsjsouza
author_rank: Super Contributor
timestamp: February 15, 2019, 08:36:26 pm
content: I know the OP is shy of more costly options from TI/NXP, but IME whatever nctnico talked is very true. The cost of the devices is offset by the long term availability, thorough documentation, SDKs, support, etc.I didn't see the AM654x family of devices mentioned here (Quad A53 plus a bunch of other stuff), but it seems their SDK supports Qt, OpenGL, etc.http://software-dl.ti.com/processor-sdk-linux/esd/docs/05_02_00_10/linux/Foundational_Components_Graphics.html

author: loki42
author_rank: Frequent Contributor
timestamp: February 16, 2019, 02:36:33 am
content: Quote from: MT on February 15, 2019, 02:14:21 pmDistro doesn't really matter at all for that as I'll just be using mainline kernel.

author: loki42
author_rank: Frequent Contributor
timestamp: February 16, 2019, 02:39:13 am
content: Quote from: rsjsouza on February 15, 2019, 08:36:26 pmThese looks like great chips apart from the abysmal GPU. Still no where near the performance of the Exynos or the price/performance of the Allwinner/Rockchip/Amlogic/Actions/etcHas anyone seen an Amlogic S905 SOM?

author: krho
author_rank: Regular Contributor
timestamp: February 20, 2019, 09:08:38 pm
content: Quote from: krho on February 15, 2019, 06:53:30 pmIt seems that you were right and I was wrong.STM32MP1

author: tom66
author_rank: Super Contributor
timestamp: February 20, 2019, 09:28:39 pm
content: Is there a reason you haven't considered Pi 3 CM3+?It has MIPI DSI 4-lane and 2-lane.For I2S you could use an external USB DAC/ADC/codec chipset -- TI make a few?

author: loki42
author_rank: Frequent Contributor
timestamp: February 20, 2019, 09:36:57 pm
content: Quote from: tom66 on February 20, 2019, 09:28:39 pmI'd love to use it apart from the I2S issue. I was looking for TDM because I need 4 channels in/out. Are you suggesting an internal USB bus? I didn't think of that.

author: loki42
author_rank: Frequent Contributor
timestamp: February 20, 2019, 11:53:41 pm
content: If there is an alternative to needing TDM I2S for multichannel (8in/out if possible, 4/4 min) I'd love to know about it. All the USB codecs that TI make appear to be stereo only.

author: tom66
author_rank: Super Contributor
timestamp: February 22, 2019, 07:52:51 am
content: Quote from: loki42 on February 20, 2019, 11:53:41 pmI'm not specifically familiar with I2S chipsets. But the Pi 3 has an onboard USB 2.0 port. If you're prepared to get "down and dirty" you may even be able to do I2S at the software level. The processor does run at 1.2GHz and writing an interrupt driven kernel driver wouldn't be impossible for a ~2MHz bus.

author: loki42
author_rank: Frequent Contributor
timestamp: February 22, 2019, 11:07:02 pm
content: I haven't found any USB multi channel codecs and I'm a bit scared regarding jitter bit banging banging i2s.