Is Xmega good for my new project?

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Hi. I develop bits and pieces for the r/c aircraft scene. I have a new idea for a project and I've designed it around a small and cheap Attiny1634. The response has been quite good, but I'm getting a lot of requests for features that the Tiny can't keep up with.

The reason I chose the 1634 was because it has two hardware USARTs. This is pretty critical. None of the Mega's have 2 until you get into big chips, and I want to keep this small (pref 64 pins or less) and cheap (must < $4 @ volume). The search quickly narrows down to Xmegas. The Xmega128A4 seems ideal really.

Here's the catch: I am not a firmware guy. At all. I rely on my beta customers to develop the firmware and then it released open and they continue to develop as they see fit. Nobody seems to have a clue about Xmega though. To me, it looks cleaner to work with... but I've never actually done any FW myself (beyond stupid hello world, blink LED, etc). Is it really that difficult?

At its base... my new project really only needs to do two simple things. If I can release FW that does those two basic things, and does them correctly, and the code is well documented... I think my customers could run with it. These are the things:

  1. Accept 9600kbaud data on UART1. Process it, package it, spit it back out on UART2.
  2. Read the state of two gpio (switches) and report that along with the above on UART2

Simple enough? Super simple? Anyone wanna make a quick $50? lol

No, serious... should I throw an Xmega on there and let my peeps loose? Or are they gonna go "WTF is that?" and run for the hills?

Also, I've read tons of (dated?) reports that Xmega's were scary buggy. Then some things that say that's been long since fixed. Is there a particular (and stocked!) Xmega that I should look at that is pretty solid?

Thanks.

- Steven

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No need for Xmega complexity. Megaxx4P/V series have 2 USARTs and are 40 pins, example m164P/V.

Quote:
Is it really that difficult?
Not really, it's more of a time/practice thing to learn programming concepts. If you can blink an led, you're almost there for doing USARTs. Look in tutorials forum.

1) Studio 4.18 build 716 (SP3)
2) WinAvr 20100110
3) PN, all on Doze XP... For Now
A) Avr Dragon ver. 1
B) Avr MKII ISP, 2009 model
C) MKII JTAGICE ver. 1

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With an Xmega, I get 8 times the flash and 4 times the eeprom for basically the same price (or less), which would be nice :)

But thanks for the 164P/V suggestion... it seems to fit. I'm not sure why that didn't show up on my Atmel parametric search? All I did was limit pin count to 64 or less, UART to 2 or more, and type to 8 bit. Maybe I just missed it.

Still, I'd like to explore the idea of the Xmega... I just need the confidence that FW can be written for it so I don't have 1000 empty shells sitting around :)

Maybe I'll try to find someone that I can pay to write it. Is there a section here for that? I didn't see it in the main index.

- Steven

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Maybe I'll try to find someone that I can pay to write it. Is there a section here for that? I didn't see it in the main index.
Trading Post forum ( trading money for skills, in this case ! ).

Steven, for baudrate you meant 9600 baud, instead of 9600k baud right ?

Original Xmegas did have ALOT of bugs, but the current series has fixed a good chunk of those.

1) Studio 4.18 build 716 (SP3)
2) WinAvr 20100110
3) PN, all on Doze XP... For Now
A) Avr Dragon ver. 1
B) Avr MKII ISP, 2009 model
C) MKII JTAGICE ver. 1

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Quote:
Process it

You omitted a few details in that step ;)

Most of what I do is for fun, and I'm certainly not much of a programmer, but I gotta say the Xmega is my chip of choice these days!

Ask yourself, do you want to be on the leading edge, or the trailing edge?

JC

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indianajones11 wrote:
Quote:
Maybe I'll try to find someone that I can pay to write it. Is there a section here for that? I didn't see it in the main index.
Trading Post forum ( trading money for skills, in this case ! ).

Thank you!
indianajones11 wrote:

Steven, for baudrate you meant 9600 baud, instead of 9600k baud right ?
Yes, of course :oops:

indianajones11 wrote:
Original Xmegas did have ALOT of bugs, but the current series has fixed a good chunk of those.
Is there a way of deciphering what is "current"? I read one article that "supposed" that those ending in UX (ie 128U4) were "fixed" but those all point to the ones with built-in USB, right? I'm sure the suppliers didn't just dump all their buggy stock.

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DocJC wrote:
Quote:
Process it

You omitted a few details in that step ;)

Bah... details... who needs em? :) Actually, very little processing. "packaging" would be a better word. The receiving side is expecting the data in specifically arranged packs is all.
DocJC wrote:

Most of what I do is for fun, and I'm certainly not much of a programmer, but I gotta say the Xmega is my chip of choice these days!
And why not!? From the datasheets, it seems obviously superior. In just the way they are logically organized if nothing else (but there appears to be a LOT else!)

DocJC wrote:
Ask yourself, do you want to be on the leading edge, or the trailing edge?
I'm with you! It just seems (unless I'm missing it) that the VAST majority prefer the trailing edge! That leaves people like me - who aren't firmware developers themselves - at the mercy of a much smaller pool of resources and talent.

- Steven

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Quote:
Is there a way of deciphering what is "current"? I read one article that "supposed" that those ending in UX (ie 128U4) were "fixed" but those all point to the ones with built-in USB, right?
Yeah, the 'U' series is the most recent AFAIK and has USB. I never dug up what all is on the fixed list, though. I would think the original buggy stuff is still on distributors' shelves.

1) Studio 4.18 build 716 (SP3)
2) WinAvr 20100110
3) PN, all on Doze XP... For Now
A) Avr Dragon ver. 1
B) Avr MKII ISP, 2009 model
C) MKII JTAGICE ver. 1