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Comment by polishdude20 | Hacker News Reader

What's the benefit of this RA4M1 processor over something like an Arm cortex ? I see the only thing that sticks out to me is the 24 volt tolerance?

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The RA4M1 is an ARM Cortex core, but it could be that Renesas offered to subsidize some of the cost of the board by providing the chips with some kind of sweetheart deal. Not a bad idea if so, Renesas can generate a whole lot of interest in their platform for what is probably a rounding error in their bottom line. And they've previously invested in Arduino (https://www.eenewseurope.com/en/renesas-backs-arduino-with-1...).

Personally I'm really stoked about the Uno finally getting a 32 bit ARM core. And an M4 at that! I would've thought maybe a M0+ (like the RP Pico) on the Uno and perhaps an M4 on a hypothetical future Mega update.

Good stuff from Arduino. The AVR on the previous Uno revs was getting quite outdated. Simple to use yes, but the Arduino environment mostly abstracts over that and only "power users" ever need to dive into peripheral registers and whatnot (eg to use interrupts).

Well, this M4 is most likely much slower than Rp2040 (2.5x difference in clock speed plus dual core). At the same clock the difference between M0+ and M4 isn't too dramatic (unless you use FPU).

I see no reason for them not to go with the RA4M2 version (with 100mhz clock and more memory). The RA4M1 Only has 32KB of memory, and slow clock. Arm M4 is a superset of M0, so clock for clock M4 should be faster. Given the price point for this board compared to the RP2040, I see no reason to give it such a limited processor.

What's the difference between an Arduino arm cortex and just getting an adafruit feather board? They have m4's on them and can be programmed with an Arduino IDE and the same tools.

Not much difference, it's just good to see Arduino coming back as decent competition.

Yeah that was my thought. Renesas Isn't a big player in the uc market at all. I don't think I've ever heard of anyone using their parts.

Back in the day, before being spun off from Hitachi, Renesas made the CPU for the original Lego Mindstorms: https://en.wikipedia.org/wiki/H8_Family

They're a big deal in industrial/automotive/defense but they don't have a ton of visibility. Perhaps why they'd be interested in more outreach, Atmel and others like STMicro definitely reaped benefits from engaging with hobby/educational users at probably negligible cost. Arduino has also been trying to position themselves as a legitimate friendly platform for industrial automation, so it could be a good match.

Renesas is (or was, at least) pretty big in the automotive sector. They are much less common in general consumer electronics, though.

i have used renesas microcontrollers in probably 20 defense contracts fwiw

How open is the toolchain/SDK for Renesas parts? I.e. can they be used with gcc/gdb/(c)make with reasonably low effort (like esp32, stm32, rp2040) or is the only realistic option using their IDE?

it's all open source, you can see part of it here https://github.com/arduino/ArduinoCore-renesas

you can use GCC with https://github.com/renesas/fsp if you want to go very low level.

their official fat sdk is a run of the mill eclipse reskin w the usual gcc ports and half working libc options last i used it :-)

What defense area? I've done a ton of random aerospace stuff and usually end up using STM or NXP. All the critical systems have been some horrifying PPC or Sparc derivative.

The RA4M1 is an ARM Cortex M4 SoC.

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