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[Reply #15 on:]

Here are the eagle files if anyone would like to review/critique/suggest improvements.
Leo72 in the Italian forum suggested using a PIC something for the USB interface.
http://www.crossroadsfencing.com/BobuinoRev17/atmega1284_DIP_NoExtras.brd
http://www.crossroadsfencing.com/BobuinoRev17/atmega1284_DIP_NoExtras.sch
I think they are in Eagle 5.11 still.

[Reply #16 on:]

Lefty, what's the diode for? I haven't used that on any board and have not seen any problems.

It was a problem that a member here uncovered about a year ago and the thread ran for some length. The findings were turned over to Massimo and they in time implemented a change in R3 UNO. It's an insidious problem that can cause a sketch to lock-up under certain conditions after receiving a auto-reset pulse from the usb serial controller, and requiring a manual reset or power down/up to recover. It can be replicated on older as well as the current (pre release 3 UNO) boards. If you look carefully at the schematic of the newest release 3 UNO, you will see they have added a diode between the reset pin and +5vdc to eliminate the problem.

I think this is the original posting and investagation of the symptom: http://arduino.cc/forum/index.php/topic,64256.90.html

Bottom line, adding a diode can clean up a lurking problem that any AVR mega chip based arduino board using the auto-reset feature can experiance.

Lefty

[Reply #17 on:]

Here are the eagle files if anyone would like to review/critique/suggest improvements.
Leo72 in the Italian forum suggested using a PIC something for the USB interface.
http://www.crossroadsfencing.com/BobuinoRev17/atmega1284_DIP_NoExtras.brd
http://www.crossroadsfencing.com/BobuinoRev17/atmega1284_DIP_NoExtras.sch
I think they are in Eagle 5.11 still.

The PIC we suggested is a PIC18F14K50, the same used for the MCP2200 chip: it's a micro that can be programmed to obtain, if necessary, other devices (like the Atmega8U2 or the Atmega16U2 of the Arduino UNO) but it is available in SOIC package too, so it can be soldered easily. Using the PIC there's another advantage: we can completely control the autoreset feature: we can activate/deactivate it, and we can send an HW reset signal to the Atmega using a pin. With a specific firmware, that a member of the italian forum has prepared, we can use the DTR signal instead of the RTS of the MCP2200. Last, but not least, we can have other functionalities available for further needs.

Bob, are these files freely available? Can we use them to derive a board?

[Reply #18 on:]

No obvious problems to my eye.

BTW, how the hell do you move the schematic around without using the scroll bars?

______
Rob

[Reply #19 on:]

On Win 7 and opening it with MS Photo Viewer, I have to grab and move it with the left mouse button.

[Reply #20 on:]

opening it with MS Photo Viewer,

An Eagle file?

______
Rob

[Reply #21 on:]

?? I thought I sized it to fit the forum, maybe just a touch wide. Can you view the .png's I posted earlier?

[Reply #22 on:]

Yes you can Leo.

[Reply #23 on:]

I thought I sized it to fit the forum,

I mean the Eagle files, how do you pan the screen without using the scroll bars?

______
Rob

[Reply #24 on:]

I generally use the scroll bars.

Or, zoom out, use the Fit button (looks like a magnifying glass) and then Select button (looks like a magnifying glass over a piece of paper) to see a selected area.

You don't have scroll bars for some reason Rob?  I have Eagle 5.11 and 6.0 installed, both have scroll bars.
If you save in 6, can't go back to 5.11 tho.

[Reply #25 on:]

opening it with MS Photo Viewer,

An Eagle file?

______
Rob

I thought you asked about the schematic .png file.  That is what I was referring to.

[Reply #26 on:]

I generally use the scroll bars.Or, zoom out, use the Fit button (looks like a magnifying glass) and then Select button

All very cumbersome though, most (all?) packages I use allow dragging the display with a mouse button as JoeO said. That's quick, easy and intuitive which probably explains why everyone except Eagle does it

I know I bash Eagle a lot but it's things like this that invite it.

______
Rob

[Reply #27 on:]

Crossroads:

I really like your "324/644/1284 style duemilanove". 

Where do you buy your surface mount components in small lots, 5 or fewer pieces?

JoeO

[Reply #28 on:]

Generally digikey.
Not  much more to buy Rs, Cs, in 10 lots to have on hand for the next project tho.

[Reply #29 on:]

How about a mostly thru-hole version?