On the right, the radio board I've been working on. Looks fairly promising, and may prove usable in its first iteration. This exact layout isn't terribly manufacturable, though; the EMI filter and balun footprints need narrowing to keep the parts from floating sideways during reflow soldering. Board size is 1" by 2".
On the left, my console/bootloader/debug adapter for Cortex-M (and some ARM7) MCUs. The yellow patch wires are bringing in Serial Wire Debug from a sawn-off LPCXpresso, to allow convenient low-level debugging; without the SWD, it's just a logic-level serial port plus the logic to drive the ISP- or BOOT* pins of the MCU, for use with lpc21isp or similar. Oh, and it can provide 3.3V and/or 5V power for the target. This board needs a significant respin, not just for the one patch wire and the chip that's no longer available in the footprint I used, but also for usability issues (e.g., that half-pitch DIP switch requires use of a mighty teeny pokey stick).
Note the skinny little 12 conductor, 0.5mm pitch flex flat cable connecting the two. When your gadget is 1" by 2", including a standard 20-pin JTAG header and DE-9 (let alone DB-25) serial port is Just Not Practical. Ergo, the mini debug interface.
At some point, now looking to be 1Q13ish, I figure to release for sale the respin of the adapter board, and some of the programmable gadgets I'm working on, probably including this radio. At that point, I'll release the specs (and EAGLE library component) for the mini debug/console connector. Might save others the trouble of re-inventing the wheel for each miniature design.
Now, if only there were an open-source SWD pod that worked with an easy-to-set-up debugger that handled various popular MCU families, I'd snarf it and create a combo pod that also included the serial/bootloader part and the FFC connector....
Update: radio platform board with 20-pin header and DE-9 for scale. Also an N connector next to the U.FL (yes, that little gold dot at top right of the board is an RF connector; there's one on the bottom, too).
(Note: clicking on the "Pin 1" marker in the image above will not cause anything to happen. Not even a Jawa's Crypt popup announcing "Nothing Happens.")
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