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Comment by jevinskie | Hacker News Reader

Well, this isn't a particularly insightful comment, but my feelings about this are "fark :[". The AVR definitely has something Nordic about it. I first learned C when programming an AVR Butterfly eval board to take photos like [0] using [1]. I've found the AVR architecture to be much cleaner than 8 or 16 bit PICs. Atmel, for the most part, embraced GPL and GCC. Microchip has tried to squirrel GCC optimization features away from being truly FOSS.

[0]: https://c1.staticflickr.com/1/53/115619170_4445c593cd_o.jpg

[1]: https://c1.staticflickr.com/1/56/112758047_dc5b4bdc3b_o.jpg

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IIRC Microchip's 8-bit PIC line had poor/nonexistent GCC support because their terrible instruction set provided no way to maintain a data stack. Their own compiler just allocated everything statically.

Granted, it's (thankfully) been over a decade since I had to use a Microchip microcontroller, and they've presumably improved since. But Atmel got it right from the start. GCC-AVR produced beautiful assembly and their ISA was a joy to use. RIP Atmel.

Calling AVR a "joy to use" is pushing it a little far. There are things to like about AVR chips as a package, but the AVR instruction set is pretty janky. I don't understand why they're so popular compared to the MSP430.

Care to elaborate?

See if https://news.ycombinator.com/item?id=10946870 answers.

I found the AVR instruction set pretty straight forward. Granted, it was my first forray into assembly and I learned it around 17 years ago at age 14. Maybe everything seems easy in hindsight at that age.

I've never programmed MSP430s in assembly, but I have for PICs and found their instruction set to be more funky than AVR.

So first a couple caveats: (1) I'm sure AVR is a hell of a let better than PIC, (2) I come at this from a really weird place (exclusively emulators and compilers), and (3) I'm not talking about the AVR parts themselves, which might be more cost-effective for a given project.

That said:

* Harvard architecture (split I & D memory)

* 8 bit registers

* Not at all orthogonal, and particularly painful for pointer addressing

* The stack pointer is annoying to work with

* Address wrap at physical memory bounds, rather than the bounds of address space

I could pick a bunch more nits that would only really be relevant to someone writing an emulator (complicated instruction decode, IO addressing, &c) but those are my big complaints.

I find MSP430 much more pleasant to work in.

Those are all true (though that an 8-bit microcontroller has 8-bit registers is… unsurprising). However I am referring to the instructions themselves, which were well-engineered to match the needs of a compiler. The result is very compact assembly for most C programs that you would write on an 8-bit microcontroller (including things like 16-bit arithmetic).

1MIPS @ 1MHZ made it popular.

PICs used to be less power hungry though and had ROM versions.

??? Sounds like FUD to me.

FUD?? Why? The did have ROM version, and, being made from slower silicon had lower leakage.

I don't know that I would say Atmel has embraced GCC. Consider the case of the AVR32: Atmel's port is in a fork of GCC, and has not been merged upstream. Considering how long they've been maintaining their fork, I'm not sure it ever will be merged.

I think AVR32 is dead (also UC3, AP7 died years ago). I've not seen any development the last years. I guess they don't want to compete with their own ARM's.

In a few meet and greets, the Atmel app engineers mentioned that they always steer people to ARM parts unless they have a requirement that absolutely doesn't fit it, then they push AVR32 parts (and seemingly hesitantly).

I believe they were working on upstreaming their changes at the time, but as the sister comment said, AVR32 never really took off and is now basically dead.

I still have a couple of AVR32 NGW100 dev boards, they were really nice to work with.

Out of curiosity, what does "something Nordic" refer to?

Total guess - maybe Nordic Semiconductor were also kicking the tyres deciding if they wanted to buy Atmel?

Iirc, Atmel is from Norway

I interpreted it as:

Elegant, clean design (certainly compared to the old 8-bit PICs). Good taste. FOSS-friendly.

Microchip might be a Texan oilman in this comparison. Just keep pumping them PICs out don't listen to those commies with their 'GCC' and their 'lee-nux' - sounds foreign and suspicious.

This is obviously a tongue-in-cheek characterisation but I think that's what the OP was getting at.

The AVR architecture was designed in Norway[1].

[1]: https://en.wikipedia.org/wiki/Atmel_AVR#Brief_history

Dude, be careful what you post. These are the days when 10-year-olds can't afford to make spelling mistakes [1].

[1] http://www.bbc.com/news/uk-england-lancashire-35354061

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