MCUs with USB in DIP package other than PICs

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I really like the USB AVRs but the only issue I have is that they are not available in DIP format. For various reasons I won't get in to DIP is preferable to TQFP.

Ruling out PICs for the moment what alternatives are there? It seems like PICs have the market to themselves. There are the ST7 series which are available SOT packages but little else.

I really wish Atmel would do a DIP package USB AVR. Just one, say in a 20 pin package like the popular ATtiny2313. I know there is V-USB but it has some limitations.

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I can only tell you what you already know.

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How many would you be using annually?
http://fletchtronics.net/bumble-b are a nice alternative for prototyping, until you get into production, when there is no reason for not using TQFP

Charles Darwin, Lord Kelvin & Murphy are always lurking about!
Lee -.-
Riddle me this...How did the serpent move around before the fall?

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Quote:

How many would you be using annually?
http://fletchtronics.net/bumble-b are a nice alternative for prototyping, until you get into production, when there is no reason for not using TQFP

Regardless of what his site says, David isn't currently producing any boards so you'd be unwise to purchase from there at the moment. I've been trying to track him down on IRC to work out what's going on, but no luck so far.

Right now the Teensy is the only option with actual stock. Just make sure you run LUFA on it instead of the Teensy examples :P.

- Dean :twisted:

Make Atmel Studio better with my free extensions. Open source and feedback welcome!

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Checkout the Arduino boards, might be what you need.

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Their website seems a bit tempremental right now but spend $1..$2 here:

http://www.futurlec.com/SMD_Adap...

for a TQFP-64 to DIP adapter.

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Perhaps have a look over at Holtek?

http://www.holtek.com/english/products/compute_8.htm

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oddbudman wrote:
Perhaps have a look over at Holtek?

Thanks, I had not spotted their offerings. They look good, although I am having trouble finding distributors.

clawson, LDEVRIES: I will be doing low volume stuff, maybe a few hundreds if I am lucky. That is one of the primary reasons for wanting DIP. Ease of hand soldering and assembly, ease of mass programming with a cheap DIP ZIF socket and the fact that I already produce PCBs for another project which are DIP and would be perfect for what I have in mind.

I have soldered quite a few TQFP ATmega168s for the Retro Adapter and while not terribly difficult it is time consuming.

Thanks for your thoughts guys.

It's a real shame Atmel don't do anything other than TQFP for USB AVRs because I already have a lot of experience and knowledge about the AVR platform and would prefer not to have to learn a new uproc and IDE if possible. Much as I hate the PIC architecture it seems that they are probably the only realistic option at hobbyist level.

On a related note I have had a couple of emails from an Atmel employee asking if I would like free samples or other support. I replied both times but have heard nothing back. I requested samples via the web site but have not heard anything about that either.

I know the hobbyist market is relatively small but it is a shame Atmel seem to be loosing interest in it :(

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The USB PICs are very easy to use, here is a design of mine with software:

http://www.leonheller.com/usb/

It could also be used with Microchip's USB libraries, of course.

Leon Heller G1HSM

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leon_heller wrote:
The USB PICs are very easy to use, here is a design of mine with software:

Thanks, I did spot your site earlier but didn't spend long there so I decided to download the source and take a look.

Aside from the other reasons I mentioned the other issue I have with PICs is their relatively poor performance. For example I want to interface with a 2MHz differential serial bus by bit-banging. Even the newer high clock rates ones have difficulty dealing with that due to high cycles per instruction and a very limited number of registers. A 12MHz AVR can do it with relative ease.

EDIT: The PIC18F13K50 or PIC18F14K50 might do. Price point and features are okay, although lack of simple ISP is a bit of a bother as it means only more expensive programmers can be used.

I am looking at doing DIP adapters with pre-soldered AVRs.

EDIT2: I should mention that the other reason I prefer using AVRs is that I have quite a lot of code already developed for them which I re-use.

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You can use a $35 PICkit 2 with PICs for programming and debugging.

You could also use a 16-bit PIC like the PIC24FJ64GB004 (DIL28). They have a much nicer architecture than the AVR, and offer more performance.

Leon Heller G1HSM

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It is difficult to decide, I need to investigate further. Ideally I was looking for a 20 pin device which is why I was drawn to the PIC18F13K50.

I just knocked up a PCB design for the AT90USB82/162. Brings all the I/O out to pin headers, on-board USB header and mini-B socket, xtal and ISP header. The I/O pins are 2.54mm spaced to be compatible with matrixboard and breadboard.

So it comes down to a choice between a familiar AVR that needs a special PCB and an unfamiliar PIC which comes in DIP package. The AVR needs slightly more support circuitry for the USB side, the PIC needs more in the way of pull-up resistors. Both work out similarly priced all said and done.

PICkit 2 looks good though. Looking at some example USB code (thanks leon_heller) it doesn't seem too bad. My last experience with PICs was before there was a free C complier and the architecture was horrible... Well, it still is horrible, but at least it supports C a bit better. The 16 bit ICs look okay though.

PS: The licensing for the MPLAB C compiler is a bit ambiguous. What if I want to use it for an open-source project that is also sold commercially? Will the free evaluation version be okay or do I need to pay for it?

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these are USB and sorta-DIP
http://www.pjrc.com/teensy/index...

I've used them. Great. Lots of good example C code.

At $18 plug and play with a ready to go boot loader, it's a great deal.

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There aren't any restrictions on the free versions of the Microchip C compilers. You lose some optimisations and large memory model, but they don't matter for most applications. The USB libraries use optimised assembler code.

Leon Heller G1HSM

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Thanks for the clarification leon_heller. I will give it a go.