[Oberon] ARM Varieties (was: Copy or reinstall A2?)

[Chris Burrows]

> -----Original Message-----
> From: Oberon [mailto:oberon-bounces at lists.inf.ethz.ch] On Behalf Of
> Liam Proven
> Sent: Thursday, 22 July 2021 12:38 AM
> To: ETH Oberon and related systems
> Subject: Re: [Oberon] Re (2): Copy or reinstall A2?
>
> > Incidentally, the Fox compiler in A2 is a cross compiler.  A
> > relatively small investment of making a back end for the RISC
> > machine would allow Fox to produce RISC object code.
>
> Which particular RISC machine do you have in mind?
>

I assumed by saying *the* RISC machine to this audience he meant
Wirth's RISC5. However, if that is so, I would not categorise the task
as a 'relatively small investment'.

> I was aware of this, yes, and I was considering trying to produce an
> experimental ARM executable and seeing if I could run it on a Raspberry Pi.
> I know it will not have any I/O without drivers for USB etc., but
> maybe if I could get as far as writing something to the screen, that would be progress.
>

Good luck with that! The ARM company have designed a wide range of
different architectures with varying degrees of (in)compatibility.

https://en.wikipedia.org/wiki/List_of_ARM_microarchitectures

AFAICS the ARM compiler in A2 targets the StrongArm architecture
developed by DEC in the 1990s which belongs to the ARM8 family.

ARM architectures used by the various versions of Raspberry Pi include
ARM11, Cortex-A7, Cortex-A53 and Cortex-A72

Regards,
Chris Burrows
CFB Software
https://www.astrobe.com