Minimal Arduino?

I prefer breadboard-friendly Arduino-compatible boards like Boarduino and iDuino, but I keep wanting functionality people have built into shields like Adafruit's Motor Shield and Batsocks' TellyMate Shield.

All I want in an Arduino:

• ATmega328
• FTDI programming header
• Arduino "form factor" with odd D7/D8 spacing and standoff holes

Sorting my Arduino-compatible board spreadsheet first by price, then by form factor, it seems the lowest price for a shield-compatible board is ~$17 for a serial Freeduino, compared to ~$10 for a Dorkboard, though the latter comes with an ATmega168, not a 328.

Necessary items:

• microcontroller: ATmega328, socket, capacitor
• clock: oscillator and 2 caps, or a resonator
• reset: 90-degree (side) button, 10K resistor
• FTDI cable interface: 6-pin header, capacitor
• Power: Barrel connector, 2-pin header

Extra interface header pin pads:

• icsp (2x3)
• i2c (4)
• spi (6) (nah)

Simple extras, parts not provided:

• Power indicator: LED, 1K resistor
• TX/RX indicators: 2 more LEDs, 2 more 1K resistors
• Power regulation: 7805, 2 capacitors, jumper
• Diode to prevent inverted power hookup

I'm traveling for the next month so this will be a fun little layout project, perhaps as a way to learn kicad (as opposed to EAGLE, which I currently use) and to explore board house pricing and specs. The goal is to be able to produce a $10 kit (cost), which may be possible given how many goodies SparkFun includes in their $20 Arduino Pro 328.

Update 12/29: I got a single-sided board laid out with just four jumpers, and I'll tear it up and redo it with the programming header where I want it, jumping TX and RX across the board. The files for the "Severino" single-sided board helped me figure out the routing.

Prioritizing Projects

Too many parts and projects lying around-- need to nail down an order and finish something soon!

PPAC should be the first priority-- I've gotten it to work, but attempts at packaging it have been held up by the fact that I'm still not sure about UI and whether I even want to use high pressure air or a pump. Would be great for a contest, but not unless it's (1) done and (2) demonstrated through video. First-things-first time:

• EAGLE: set up with display, jog/shuttle, RTC, buttons, switch, power, and output. Don't worry about whether output is to relays or oo's,
• Arduino: get a good program working on the breadboarded circuit,
• Figure out best fill/empty plan,
• THEN start laying it out in 3D for the final build.

Next up (while figuring out ppac fill/empty plan) is a working growduino with relays, no sensing, no logging, and no solar-- don't try everything at once! Better to get something growing.

The invervalometer is so close, but needs:

• To be reeled back to the breadboard after the stuffing problem-- Arduino OK?!
• Panasonic-capable trigger,
• Serious power system consideration.

The mutetater should be a simple build:

• Limit to Sony since that's easy to read, and I have Samid's old Sony TV,
• Breadboard > potato should be simple using a dorkboard with female header pins.

Comprehensive Arduino-Compatible Hardware List?

I can't find a complete list anywhere, so here's my stab at it, starting with the list at arduino.cc, Make's 2008 Arduino Gift Guide, Freeduino, Adafruit, Sparkfun, Seeed Studio, RepRap, Wulfden, [more]. Not sure about the Orangutan and mpguino since not all pins are exposed, and unsure of Teensy boards since they need custom Arduino IDEs.

Update (June 16): I revised the spreadsheet and messed around with font and cell sizes to make it more easily viewed in-line here, plus it should update automatically as I add or edit boards. Happy hacking!

Update... ALL THE TIME!: This is constantly being updated as new Arduino-compatible boards are announced!

Click here for the spreadsheet on its own in Google Docs.