New RTEMS user..

[Ian Caddy]

Hi Patrick,


On 7/09/2018 1:39 AM, Patrick O'Banion (TMMC) wrote:
> ~/development/rtems/5
> ~/development/rtems/src/kernel
> ~/development/rtems/src/kernel/erc32
> ~/development/rtems/src/kernel/rtems
> ~/development/rtems/src/rtems-source-builder
> Etc..
>
> If I build a new set of build tools, can they share these directories?  I expect I will get a second set of "arm" build tools in my "~/development/rtems/5/bin" directory.  I can see how in the src/kernel I can create a new build directory.  For example "~/development/rtems/src/kernel/arm" and recompile rtems for an arm processor there without disturbing the erc32 build.  But what do you typically do for the tools?  I could archive them in a new directory or just change the dir name to something erc32 specific...  There are probably numerous ways to handle it, I was just wondering if there is a standard method most rtems users prefer.

I have not used two build trees on the same RTEMS version before, so 
can't really help here, but I would imagine that they would all fit OK 
in the same directory structure as all the specific build tools are 
named with the processor type.  Maybe other can comment on this better.

> 2. My final targets are an adafruit M4 Metro (https://learn.adafruit.com/adafruit-metro-m4-express-featuring-atsamd51/overview) and an adafruit Trinket Pro (https://www.adafruit.com/product/2000).  Could someone maybe help suggest the closest BSP for these boards?  I don't mind attempting to build/modify the BSPs.  I think with some help from the rtems community and google I could do it.
The ATSAMD51 is a Cortex-M4 processor, which is a ARMv7-M architecture.  
We use Cortex-M3 and M4 processors but not with RTEMS, as their memory 
footprints are quite small.  Your closest BSP in RTEMS5 would be, 
according to :

https://devel.rtems.org/wiki/TBR/Website/Board_Support_Packages

The NXP LPC40XX, but looknig in the current tree I don't see a 
rtems/bsps/arm/lpx40xx  maybe someone else can point you to one of them.

The next closest would be the Cortex-M3 (but if you want floating point 
hardware support you will need to change the compiler options).  Look at 
the following:

rtems/bsps/arm/lpc176x
rtems/bsps/arm/lpc176x

I just noticed that the:

rtems/bsps/arm/lm3s69xx

contains at least one Cortex-M4 config which is for the LM4F120.

Also the Atmel, now Microchip peripherals are quite different to the NXP 
and others, so you might be able to share some code from the:

rtems/bsps/arm/atsam

Maybe the peripherals are the same or similar.

regards,

Ian Caddy