It's alive!
----
  amforth 7.0 CORTEX-M4 UNO R4 WIFI
 Mon Jan  5 00:01:19 EST 2026 ## unor4...origin-unor4
> 3 4 +
 ok
> .s
1  7  ok
----
Haven't really done much with it, many things may still need fixing, but it
is finally responsive.

Many lessons learned in the process, here are some highlights:
* the board datasheet is completely inadequate, just figuring out which SCI
interface is used for communication was a pain. I ended up going into the
arduino bootloader and usb-bridge sources to figure out what settings to use
* figuring out the relevant clock frequencies that the chip is running with
and then calculating the bit rate settings wasn't exactly walk in the park
either, but the RA4M1 datasheet and user manual are really quite good.
* pretty much all the MCU modules, including the SCIs are stopped after
reset; in this state reading any of the SCI registers just returns 0 and
writing them doesn't do anything.
* the status bit that you need to poll for transmission doesn't kick in
until you send the first byte through (when the byte moves from the data
register to the shift register). the workaround is to just write the first
byte without polling right at the start
* Google AI was actively detrimental in my searches for answers, it would
consistently provide wrong answers and argue with me when I pointed out
discrepancies with what I already knew. In desperation I tried Grok towards
the end and it was spot on; it was Grok that told me about the stopped
modules when I described the symptoms, I didn't think I needed to read the
low power mode chapter in the user manual at this point which seems to be
the only place this feature was mentioned.

Anyway, I'd be happy to now focus on polishing what I've got to get it to a
state worthy of contributing back. The code is heavily commented, just to
save me from forgetting things too quickly. I'd be inclined to keep most of
it if that's ok. If I could get some guidance from the maintainers, I'll do
what's requested. I've opened a pull request in my repo showing the current
state; figured that might be the easiest way to gather feedback and discuss
changes https://github.com/mkobetic/amforth/pull/1. We can move the changes
back to the SVN repo once we are happy with the result.

Cheers!

Martin

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