Re: Should light runtimes get more consideration?

[DrPi <314@drpi.fr>]

Le 29/09/2023 à 12:42, Chris Townley a écrit :
> On 29/09/2023 10:59, Kevin Chadwick wrote:
>>
>>>>>> Tasking is very limited. For example you can't use
>>>>>> timeouts. Never. They propose a workaround but it is complex and not
>>>>>> equivalent to a real timeout management.
>>>>>
>>>>> Not sure what a "real timeout management" would look like?
>>>>>
>>>>>> I'd like to have a full Ada RTS for embedded targets, like on
>>>>>> desktop.
>>>>>
>>>>> Have you considered using something like a Raspberry Pi?
>>>> A RaspberryPi is a computer (based on a microprocessor with an OS), 
>>>> not an micro-controller. It consumes a lot of electrical power. The 
>>>> OS (linux) is not real time. It uses a lot of board space. The 
>>>> processor is a proprietary black box...
>>>>
>>>
>>> Plenty use the Raspberry Pi as a microcontroller
>>
>> I think Simons point was that Arm/Linux has a working full runtime. I 
>> guess
>> bare raspberry pie would not and I guess it would be a rather large 
>> module
>> or board or single board computer depending on the model.
>>
>> WRT energy use. I use a low power run feature on the STM32L4 which 
>> means the
>> system clock speed can change at any time. That seems to be incompatible
>> with any runtime that I have seen except the minimal light-cortex-m4 
>> one. I
>> assume working with clocks is more scalable than working with runtimes 
>> but
>> I do not know for sure.
>>
> 
> Agreed, but in addition to the mainline Pis there is the zero, and the 
> pico, which has a 'RP2040' made by Raspberry Pi and is a dual-core ARM 
> Cortex M0+ processor, with a flexible clock running up to 133MHz
> 
A runtime for the RP2040 already exist. It is based on the Adacore ARM 
runtimes so has the same limitations.