The Freescale Freedom development boards come in several different flavors and at several different price points. It is pretty clear that Freescale counts up pennies to hit their desired target price. For example, the costlier boards with bigger processors (like the K64F which costs about $35) has sockets to fit an Arduino shield or other external connections. Many of the cheaper boards (like the KL25Z for $13) just has PCB holes. If you want to add sockets, that’s on you.
The $30 K22F board has the sockets, but it also omits a few components that are on the PCB. [Erich Styger] noted that there was a micro SD card socket footprint on the board and wondered if he could add an SD card to the board by just soldering on the socket. The answer: yes!
Other boards use a similar socket and [Erich] identified it as an SD-105027-001 (PDF) from Molex–a dollar part. Soldering the socket on the board wasn’t too hard since the pads have some solder on them already. [Erich] used some additional solder paste and notes that the corner ground pads under the socket are the hardest to get to. You’ll need a thin iron tip.
The board wouldn’t be a bad platform to build the signal generator project we covered earlier that used the K64F). The K22F has 128K of RAM, 512K of flash, and can run at 120MHz. It even has a floating point unit on board. Not bad for $30.
We’ve covered how to get started with mbed on a KL25Z (see the video below, also) and using this board would be almost exactly the same. You just need to select K22F as the target and account for any I/O pin differences. In addition to that tutorial and the signal generator, we’ve also looked at using a similar board as a mouse (coincidentally, another project from [Erich]).