[Ovmsdev] OVMS v3 - Microcontroller

Thu Feb 4 03:28:44 HKT 2016

Speaking of modularity, how about having 1 or 2 CAN buses standard
built-in, and additional CAN buses being optional add-ons? The additional
CANs could be MCP2515 based via SPI, like
http://www.mikroe.com/click/can-spi-3.3v/.

With plenty of speed, flash, RAM and I/O pins, the software can tidily
abstract the SPI comms so that CAN rx/tx functions appear the same whether
built-in or module-based.

The advantage I see is that it doesn't constrain the primary MCU selection
so much, and there are plenty of options available today. Many people will
be happy with 1 or 2 CAN channels, and those who want 6 CAN channels will
happily pay an extra $100 for the additional hardware.

-Arthur

On Tue, Feb 2, 2016 at 11:10 AM, Julien Banchet <jaxx at jaxx.org> wrote:

> Mark,
>
> I'm a bigger fan of standardized LoRa networks than SigFox but was going
> to share the latter's little faire in London on Feb 16th until I realized
> you where in HK and not UK.
>
> Nevertheless, I bet it might get some curious on the list :
>
> http://makers.sigfox.com/tour/
>
> They have already deployed in 10 major agglomerations (Londres,
> Manchester, Liverpool, Birmingham, Glasgow, …) and are still extending.
>
> JB./.
>
>
> On Mon, Feb 1, 2016 at 2:35 PM, Mark Webb-Johnson <mark at webb-johnson.net>
> wrote:
>
>>
>> Well, the new year is here and OVMS v3 is on the front burner now.
>>
>> As you know, I’ve been waiting for the MBED system to settle down and the
>> news is … it hasn’t. Sure, they’ve finally released some open beta code,
>> but only really 1 board supported. No more online compiler. Complicated
>> tools. RTOS worse than the old MBED. And worse is a proprietary
>> closed-source server platform for their Internet-of-things MBED O/S.
>> Luckily, the one board they support is the NXP FRDM-K64F that I love. I’ve
>> tried it, and it sucks. Maybe in a year’s time…
>>
>> I’ve been waiting and waiting for this. Can’t say how disappointed I am
>> with the whole direction of the MBED project and closed development,
>> closed, source approach.
>>
>> Anyway, OVMS v2 is end of life. We can’t get the SIM908 GSM modules any
>> more. Even if we could, 2G really doesn’t have that much longer. There are
>> a lot of M2M devices out there, but the frequency space is just too
>> valuable. Over the next year or two, more and more 2G capable cell towers
>> are going to be turned off.
>>
>> So, time to take the plunge and get on with it. I’m guessing an open
>> source development environment, some free RTOS, and an adapted boot loader
>> to allow us to flash from SC-CARD, USB, or something like that.
>>
>> From an overall system architecture point of view, I think we know what
>> we want. A board with a fast micro controller, lots of ram and flash,
>> several CAN buses, and easy development environment, easy firmware upload
>> for the novice, SD card, USB, ethernet, wifi, bluetooth, and some digital
>> I/O. Then, expansion slots to plug in 3G/4G connectivity and whatever else
>> we want.
>>
>> We’ve now got lots of options on the wifi+bluetooth front. Within the
>> next couple of months, the ESP32 is going to be out, and that looks really
>> nice. Same story with 3G/4G modules. I don’t see this as an issue.
>>
>> So let’s discuss the micro controller.
>>
>> Let’s say we want at least 1MB flash, and at least 256KB RAM. At least.
>> Now, we need multiple CAN ports. 2 at a minimum, but 3 or 4 would be much
>> better. A lot of the newer cars split their stuff over multiple CAN buses,
>> and having that support would be great. Remember that we want one system
>> that can be used as a logger, development environment, and final production
>> system. That puts us in ‘automotive’ territory, which is not a bad place to
>> be.
>>
>>
>>    - ST have some brutal micro controllers, like the STM32F769. M7 core.
>>    Up to 2MB flash, 512KB SRAM, and 3x CAN buses. All the older stuff is 2 CAN
>>    bus max, but availability of the new 3xCAN bus stuff is summer 2016. A
>>    couple supposedly available now, but I can’t find them.
>>    - NXP have a nice automotive range in the MPC micro controllers (in
>>    particular MPC56 has lots of choice, and 10 year product life time), but a
>>    strange e200z0 core that I’ve never seen/used. Again, brutal on the flash
>>    and RAM, and up to 6 CAN buses. These are their SPC5 32bit automotive MCUs.
>>    They have a ‘free’ GCC based development environment.
>>    - The NXP S32K looks good, but seems not available yet.
>>
>>
>> My preference is the NXP range, but I am concerned about that e200z0
>> core. Really never heard of it. Anyone got any experience with this?
>>
>> The ST stuff also looks good, but availability is tight.
>>
>> Thoughts? Anybody have a good contact with NXP for some advice?
>>
>> Regards, Mark.
>>
>>
>>
>>
>> _______________________________________________
>> OvmsDev mailing list
>> OvmsDev at lists.teslaclub.hk
>> http://lists.teslaclub.hk/mailman/listinfo/ovmsdev
>>
>>
>
> _______________________________________________
> OvmsDev mailing list
> OvmsDev at lists.teslaclub.hk
> http://lists.teslaclub.hk/mailman/listinfo/ovmsdev
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openvehicles.com/pipermail/ovmsdev/attachments/20160203/d0d267f4/attachment.htm>