[Openmcl-devel] Challenge: CCL port to the RPi Pico (RP2040)

[Jon Boone]

For those who might be interested in such a project, where would one start?

— jb
On Jul 28, 2024 at 10:54 -0400, Tim McNerney <mc at media.mit.edu>, wrote:
> The popular Raspberry Pi Pico chip (RP2040) is a remarkable microprocessor with memory resources not dissimilar from the Mac 512k, CCL’s debut target. Here are some quick facts.
>
> • > Dual ARM Cortex-M0+ @ 133MHz
> • > 264kB on-chip SRAM in six independent banks
> • > Support for up to 16MB of off-chip Flash memory via dedicated QSPI bus
>
> Some might argue it’s not comparable to a Mac 512. I claim it is: consider that the RAM would only used for the heap, stack(s), and housekeeping? It is the off-chip flash support that makes all the difference. That’s where you can store static code and data segments that make up the bulk of a CCL image.
>
> My big questions:
>
> 1) Could this chip run CCL?
>
> 2) Would it be worth the effort?
>
> I think yes on both fronts. A lot of embedded code is truly modest, so a small heap is useful enough. This is the arena where microPython shines—itself sporting a garbage collector.
>
> 3) Does anyone want to try?
>
> CCL already has 32-bit ARM support. There is no OS interfacing work to do here (only work to make up for the lack of OS).
>
> This could be a fun little project that would a great way to become familiar with CCL internals without a lot of distractions from OS and GUI issues. First get it working from a serial port console (over Bluetooth maybe?) and focus on embedded applications. Slash and burn the rest, at least for starters.
>
> --Tim
>
> > On Jul 28, 2024, at 01:32, R. Matthew Emerson <rme at clozure.com> wrote:
> >
> >
> >
> > > On Jul 27, 2024, at 8:23 PM, Grégory Vanuxem <g.vanuxem at gmail.com> wrote:
> > >
> > > In FriCAS  built on top of Clozure CL I obtain this output in a terminal (WSL2)
> > >
> > > (gamma(x) âÃÂàreals && Re(x) > 0) || (x âÃÂàintegers &&
> > > gamma(x) âÃÂàreals)
> > >
> > > instead of (SBCL)
> > >
> > > (gamma(x) ∈ reals && Re(x) > 0) || (x ∉ integers && gamma(x) ∈ reals)
> > >
> > > if I (print ...) a string with, for example, ∈, in a pure Clozure CL
> > > (recently git cloned) this is correctly printed, no problem.
> > >
> > > So I wonder if I have to modify the output stream character encoding
> > > or the output routine.
> >
> > Check that the external format of the FriCAS output stream is what you expect. In other words, if you pass an explicit :external-format argument to cl:open, make sure it matches what your terminal requires.
> >
> > Doing (describe *terminal-io*) might show something interesting. Here’s what it shows for me:
> >
> > ? (describe *terminal-io*)
> > #<ECHOING-TWO-WAY-STREAM input #<BASIC-CHARACTER-INPUT-STREAM UTF-8 (TTY/0) #x1824C7D6>, output #<BASIC-CHARACTER-OUTPUT-STREAM UTF-8 (TTY/1) #x1824C2A6> #x1825FBE6>
> > Class: #<STANDARD-CLASS ECHOING-TWO-WAY-STREAM>
> > Wrapper: #<CLASS-WRAPPER ECHOING-TWO-WAY-STREAM #x18039A16>
> > Instance slots
> > SHARED-RESOURCE: NIL
> > OPEN-P: T
> > INPUT-STREAM: #<BASIC-CHARACTER-INPUT-STREAM UTF-8 (TTY/0) #x1824C7D6>
> > OUTPUT-STREAM: #<BASIC-CHARACTER-OUTPUT-STREAM UTF-8 (TTY/1) #x1824C2A6>
> >
> > The default external format has been #<EXTERNAL-FORMAT :UTF-8/:UNIX #x18249C6E> for quite a long time now.
> >
> > https://ccl.clozure.com/docs/ccl.html#characters-and-external-formats
> >
> >
> > >
> > > And more importantly, how can I achieve that?
> > >
> > > - Greg
> > >
> > > PS:
> > > (1) -> )lisp CCL:*DEFAULT-EXTERNAL-FORMAT*
> > > Value = :UNIX
> >
> >
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.clozure.com/pipermail/openmcl-devel/attachments/20240728/118c9f14/attachment-0001.htm>