2013-05-27

LogicBoost part 2

So the LogicAnalyzer did work OK, and just needed a proper USB-to-UART converter to be used properly. What could possibly go wrong?

Enough, it turns out.

As described in the first part, I added fixed connections to one of my Launchpads to cross the Tx and Rx lines between the MSP430 and the Launchpad (to be able to use the G2553 together with the Launchpad as USB-to-UART converter). This meant I could not use the Launchpad in question when using the MCP2200 because then the Launchpad and the MCP200 would conflict. No problem, I had another one available and used that one.

But what I did forgot was that, by default, all the jumpers are populated on the programming header. And this includes the jumpers for Rx and Tx. That meant that as soon as the programming is finished, the G2553 starts up and tries to use its UART lines. And since they are connected to the Launchpad lines - boom.

Whats even more worse was that I didn’t recognize the first time. I just saw that the ‘2553 did not communicate with the PC. So I used a logic probe and found that it didn’t send anything back (neither high nor low signals). So I tried to program another G2553 - and fried that one too…

Since these were the only two of its kind in my boxes, this meant putting this project on hold and wait for replacement. In the meanwhile, I at least properly connected the MCP2200 converter to the LogicBoost. I just used our wires - three of the going to the FTDI header on the LogicBoost board, and the 3.3V line to a place nearby (even though the FTDI modules have a 3.3V line, the corresponding pin is not connected on the LogicBoost board).

Posted by Hendrik Lipka at 2013-05-27 (Google)
Categories: electronics tools