Project idea - MSP430 BSL

Did you know that in the TI MSP430 Value Line (G2xxx series), especially the ones which offer 512B RAM in addition to the JTAG and SBW contains a serial BSL (bootstrap loader) ?I didn't. I realized this a few weeks ago. Since then I've an idea that I use in my next project (I've also a project for it now , but it does not belong here).The serial BSL have conditions. The device must be switched to this mode. In order to do this, however, the usual three-wire (RX , TX, GND) serial port is not enough, because you must use the TEST and RESET pins to achieve it.In addition, the problem is that today's computers are no longer has serial ports, and if  it has, the level shifting would be an issue (an addition MAX3232 required as minimum).So what we need is a USB port. The BSL solutions can be found on the internet typically has MCU and use lot of code in it. I thought that I approach the question differently. I'm going to use some USB/UART converter chip, which is able to produce additional signals to these three-wire serial port. It would be obvious to use some FTDI chip, but I haven't found that any what available at low cost.As I'm looking around, found two candidates:

• Silicon Labs CP2102/2104
• Microchip MCP2200

Why would they be capable for the task? Because both USB composite devices which in addition to the serial port has a HID device with 4/8 bit GPIO. This can be good for handling the TEST and RESET lines.The first of this two chips are not looks suitable for home made stuff, because the QFN package is not really kitchen table compatible (home soldering). I did not throw it out because it can be purchased as a ready made module for reasonable price (at pololu http://www.pololu.com/product/1308 and of course on eBay as well). On the other hand the second, however, seems to be an absolutely good choice (https://shop.chipcad.hu/Welcome/Default.aspx?scenarioID=360&search=mcp2200&searchShowSaldo=false&type=0) the prices start at $1.4 net.Both have (hopefully usable) PC API so there's no need to bother with the direct USB programing.So the idea of the project is as follows:Create a (two) reference circuit design along with a C# downloader for the MCU programming.