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[Reply #330 on:]

Not at all, my design brings out all the usable pins and includes optional external pull up resistors like the R3 ProMini by Sparkfun, but your design is a good idea also.
BTW how do you plan to connect all the additional tx/rx and input/output pins when confined to 28 pins?

What I mean is that electrically it is the same....

All the extra pins are simply wasted on this board, it is just a sketch space increase :-)

I could take the extra pins to a header on the board but this is not for that reason.

[Reply #331 on:]

Not at all, my design brings out all the usable pins and includes optional external pull up resistors like the R3 ProMini by Sparkfun, but your design is a good idea also.
BTW how do you plan to connect all the additional tx/rx and input/output pins when confined to 28 pins?

What I mean is that electrically it is the same....

All the extra pins are simply wasted on this board, it is just a sketch space increase :-)

I could take the extra pins to a header on the board but this is not for that reason.

That's what I thought but you know what they say about assuming.

[Reply #332 on:]

Sent out a ProMighty to Maniacbug now lets see how fast mail delivery from Alaska to Washington is.

[Reply #333 on:]

woohoo!  Got a copy of CrossRoads' basic duemilanove-style 1284 board working and uploading via ICSP (Olimex AVR-ISP500)... Don't own an FTDI cable, it's coming in the next Mouser order early this week, but I have this baby soldered up and clocked at 20MHz.

Managed to do a typical LED blink, and with the USART, 5V and GND pins hooked to my old Arduino NG (w/ Arduino IDE pointing to its serial port rather than the Olimex programmer), managed to get serial output from the 1284 running a sketch to read a bunch of DS18B20's I have.

[Reply #334 on:]

Nice job!  Post a pic when you get a chance.

[Reply #335 on:]

Took a pic-

http://spirilis.net/junk/arduino/bobuino/dsc_4683.800.jpg (source high-res JPEG: http://spirilis.net/junk/arduino/bobuino/dsc_4683.jpg)

The LEDs I had in my stash were too big, so the TX LED ended up sticking above the headers... so I desoldered it, rather poorly (ended up destroying the pads on one side) but oh well, that's why I have 2 (and a set of smaller 3mm LEDs on the way, including some blue ones for a touch of "Pimp My Arduino")
The 3V3 regulator was another mishap... accidentally ordered the 5V variety, desoldered that much more successfully.  Got 3.3V ones on the way along with the FTDI cable, LEDs, bunch of other junk too.

Here's the finished bobuino with my other blank board (and the debug shield for my car buffered-I2C/OneWire network up top)-
http://spirilis.net/junk/arduino/bobuino/dsc_4678.800.jpg

[Reply #336 on:]

ended up destroying the pads on one side

I know most people here prefer PTH  but when it comes to de-soldering SMDs are much easier.

______
Rob

[Reply #337 on:]

It is as easy to desolder TH if you physically destroy (with a cutter) the component, leaving just the pins, then desolder those one by one. Wick and flux will also help.

[Reply #338 on:]

ended up destroying the pads on one side

I know most people here prefer PTH  but when it comes to de-soldering SMDs are much easier.

______
Rob

I am starting to agree.  Also SMD capacitors, resistors are so darned dirt cheap (and IMO 0603 parts are easier than hell once you've done a few, I don't even use my magnification visor anymore, just a steady hand)... I can appreciate CrossRoads's use of PTH parts to make the kit accessible to relative newcomers though.  And for the price and effort (as you can see with mine I left out all the DC jack and regulation, just don't want/need it) his board is a wonderfully cost-effective way to roll a dev (or hobby-production use) board IMO.

[Reply #339 on:]

I can appreciate CrossRoads's use of PTH parts to make the kit accessible to relative newcomers though.

Agreed, and to be sure a socketed DIP is a lot easier to replace than a TQFP when you blow it up

______
Rob

[Reply #340 on:]

Looks like a good start spirilis. Have to look close to see where you changed things.
The polyfuse - that looks really small, is that the 500mA part?

Am thinking now I could have spread the LEDs out a little more to allow for 5mm part as well.

[Reply #341 on:]

Looks like a good start spirilis. Have to look close to see where you changed things.
The polyfuse - that looks really small, is that the 500mA part?

Am thinking now I could have spread the LEDs out a little more to allow for 5mm part as well.

Only real changes are leaving out the stuff in the lower left, and using a 20MHz crystal instead of 16... The polyfuse I used was this: http://www.mouser.com/Search/ProductDetail.aspx?R=NANOSMDC050F%2f13.2-2virtualkey65000000virtualkey650-NANOC050F%2f13.2-2

I'll solder a pin header on the FTDI pins soon since I'm getting an FTDI cable this week.

[Reply #342 on:]

I've been using 16MHz crystals.  What is the timing like with 20MHz parts ?  Are there any timing issues as I had been led to believe?

[Reply #343 on:]

It is as easy to desolder TH if you physically destroy (with a cutter) the component, leaving just the pins, then desolder those one by one. Wick and flux will also help.

To be honest I don't think either are easier to deal with than the other anymore.

With ChipQuik it is ridiculously easy to whip off an SMD IC and with a vacuum desolder station it is just as easy to do each pin of a PTH.  They are very cheap now!

SMD resistors, small caps, diodes & transistors are simplicity itself to solder if you learn how and all you need is a normal soldering iron and some decent tweezers especially 1206 size.

SMD chips are no more difficult than PTH again it you learn the technique.

The issues come with: stuff that shows you little of the contact so some kinds of SMD ICs, some resonators & crystals, electrolytic caps, tiny presets; very fine legged ICs like 2560s etc and special stuff like BGAs etc.

[Reply #344 on:]

I am having a hard time with the FTDI FT232RL chips. Have 4 of the original Bobuino's, requests for 3, having a hard time getting them soldered without shorts.  That was a big driver behind making this board and going with a USB/Serial module vs discrete parts.