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Comment by blueflow | Hacker News Reader

How can the Arduino boards be obsolete? I still use nano clones because they are cheap AVR m328p boards with a fine power regulator and a sane quartz.

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What's the point of using an eight bit microcontroller if you can get something that's order of magnitude more capable for the same price?

Power usage, for one.

AVR chips are among the worst for power consumption. An Atmega328p will draw ~24mA at 16MHz.

Compare that to an Atmel SAM-L that draws ~400uA (0.4mA) at the same 16MHz, and is on a 32-bit Arm Cortex platform.

Isn’t that mainly due to process nodes?

Assuming I hadn't failed at basic maths, the absolute max power consumption for RP2040 (implementing a media player) is 130mW, but the average power consumption in a more typical scenario would be 14mA at 48MHz.

AVR is much simpler architecture-wise, and this has the more impact the more you actually need to read the processors datasheet.

Have you actually compared the datasheets for AVR and RP2040?

RP 2040 is a board, not a processor. Did you compare an AVR datasheet with the ARM Cortex M0 Datasheet? ARM generally can't win this specific game against AVR.

RP2040 is a SoC, not a board.

So, have you?

Yes i have, and ARM is significantly more complex than AVR.

If you want to be more specific, AVR has no exceptions/faults and the interrupt priority is hardwired.

Edit: And AVR has only one encoding for instructions, not a big and a small one.

Why not the other way around? What's the point of using a dual core 32bit with hundreds of K of ram for, let's say, a simple automated irrigation controller? There are applications for both.

Yeah, it's funny how long-lived chips are in the embedded world. I think a lot of it comes down to inertia and familiarity. "If it ain't broke...". I see that with keyboards, for example, that like you said often still use atmega 328s. That said, if you just look at features versus price (specially if you're not buying at volume) there's a lot of nice things you can get for basically no extra cost (or even negative cost) in newer versus older chips.

AVR is still fine for many uses but it's a 16bit controller. You can now get 32 bit ARM boards for about the same price, with more memory and better tooling. If starting from scratch, there's no reason to go with AVR.

> AVR is still fine for many uses but it's a 16bit controller.

Isn't it 8-bit?

AVR can run at 5V and has 10mA drive on it's pins. Sometimes that matters for what you need to interface with. The newer chips with integrated USB have nice features like a high speed 64MHz timer and the serial port is free of conflicts.

Cool. The RP2040 can put up to 12mA, and it's adjustable per pin.

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