Mindboards

Crossposting this to Mindstorms Software because I think it pertains to both equally. Apologies if I'm wrong.

So, I was looking at the NXT's specs and comparing it to some other hardware, and came across this part of the Wikipedia article:

...It has a 32-bit ARM7TDMI-core Atmel AT91SAM7S256 microcontroller with 256KB of FLASH memory and 64KB of RAM, plus an 8-bit Atmel AVR ATmega48 microcontroller...

I was extremely curious here. I'm not familiar at all with these sorts of chips, but from what I understand, the Arduino Uno has an 8-bit Atmel AVR ATmega328, with internal specs of 32KB FLASH memory and 2KB of RAM.

I was wondering what part of the NXT is running the code, and what part is running the OS? In other words, if I write a program and execute it on the NXT, what sort of system specs am I actually dealing with? According to google, the ATmega48 has 1/8th the FLASH memory and 1/4th the RAM compared to the ATmega328. But then, there's still the AT91SAM7S256 in the NXT.

If I write code and port it to the 'duino Uno, will my available specs go up or down?

Very confused here!

Hey,

The ATmega is only used to control the motors and read the standard analogue values. It communicates with the main processor, the ARM7, every 3ms or so, over a high speed I2C bus. The ATmega chip is not user controllable and just has a small firmware on it that is only upgradeable if you have a ICSP device (programmer). Don't mess with it.

The code you write in NXC, ROBOTC, Lejos or whatever, all run on the ARM7, not the ATmega.

Regards,
Xander

Edit: I deleted your other post, because it was identical to this one. Please don't cross post.

@Stryker,
NXT != Arduino

on AVR Arduinos, you may even use the seperate Atmega 16u2 USB communication controller additionally to the Atmega 328P main processor for your personal programming.

OTOH, NXT is more like Apple: high walls and holy gardens

HaWe wrote:NXT != Arduino

correct. However, there are comparable chips inside (atmegas) which is what I was curious about.

From what Xander says, it seems going from an an NXT to an Uno will result in a severe drop of processing capability....

also Apple uses standard chips

but about the AVR: IMO not a drop.
more a complete loss.

HaWe wrote: about the AVR: IMO not a drop.
more a complete loss.

>.< yeaaaah. I'll have to re-write my fluid sim and see if it even runs on an Uno. If not I might be back to square one... Again...

are you also using Arduinos to be connected to NXTs, like I do ?

HaWe wrote:are you also using Arduinos to be connected to NXTs, like I do ?

Haha no, I wish I had that sort of hardware!

I've used an NXT in the past, and I'm looking at purchasing a Peggy 2LE from EvilMadScientist ( http://www.evilmadscientist.com/2009/peggy-2le/ ) but the processor on that one is apparently equivalent to the Arduino Uno's processor. A friend has an Uno clone, so I would be able to test code on that... But I dunno if it's beefy enough xD

But you still got a NXT, no?

Arduinos are for 5 USD (Uno) or 10 USD (Mega) up to 15 USD (Due) if you wish to buy a China Clone.
By Unos you can control +2 extra encoder motors + 4 analog sensors
by Megas +6 encoder motors + 8 analog sensors + 16 touch sensors + 1 PS2 PC keyboard
by Dues the same +1 extra standard/highspeed i2c Port (for >110 I2C devices) +1 extra SPI port.

The only lack is: - issues about TFT displays and issues about non-volatile memory, but I'm about to fix this.

ps, this is my current state of work:
http://www.mindstormsforum.de/viewtopic ... 302#p65015

HaWe wrote:But you still got a NXT, no?

not currently xD

It's on the other side of the country right now and I have no idea if/when it will ever get shipped out here...