Embedded board with good support out of the box?

[Mr. Andrei Chichak]

On 2015-May-22, at 8:58 AM, Steve B <sbattazzo at gmail.com> wrote:

> The STM32F4 is on my list, but because our main number-crunching routine already takes 25% of our time step duty cycle on the AM3358 at 1GHz, it seems risky. If we pretend MIPS/MHz and FLOPS/MHz were a 1:1 map from the A8 to the M4, then we are guaranteed to violate timing. On the flip side, this number crunching part is not in any way optimized with embedded operation in mind, so there are at least a couple things I can think of  we could do that may allow us to squeeze it in to a Cortex M device.

I think 1:1 would be optimistic, but you also don’t have to deal with a heavy OS or things like demand paged virtual memory. 

It is a bunch of effort getting together the boards,  getting stuff to compile, getting a debugger working, load the code, figure out that you need a null modem cable for the serial port, and figure out what RTEMS gives you and what it doesn’t. Oh, desktops and Arduinos, you have raised peoples expectations so high, on the other hand we’ve been busy for the last 10 years.

> I think at the very least I will grab a couple of those discovery kits and rig up a dummy loop application and get CAN bus running and see how that goes, but I was hoping that there might be a good drop-in replacement with similar horsepower to what we already have. I’m not hurting too much for physical size or power budget, so I thought a small x86 board might be good if it already has the drivers we need and can be brought up with minimal effort.

On my current project we are using a J1939 (large vehicle data) stack on top of CAN on a STM32F407. I used ST’s program called CubeMX to generate the initialization code for the various subunits (including the horrible task of firing up all of the various fine grained clocks) and their abstraction library code (with reasonable examples) and bringing up the CAN bus was about a day.

More complex tasks like getting a 1KHz timer to trigger the ADCs to convert 14 channels, then generate a DMA event, took a little more setup time, but no CPU time.

Andrei