I tend to leave Tera Term up and working as I do software development on a FRDM board and periodically experience the problem of having the Tera Term's font being inadvertently changed during FRDM OpenSDA programming by an accidental VT100 "SO" (Shift Out) command being sent as a programming string. Tera Term works as a VT100 (or other terminal) emulator so this isn't something you can easily disable.
I figured out a simple preventative measure for it; in KSDK2, after the "BOARD_InitDebugConsole();" statement in "main.c", add:
PRINTF("%c%c", 0x16, 0x0F); // Send VT100 "SI" Character String to Console
This will ensure that normal ASCII characters are displayed during program execution.
To show what I mean, in the Term Term Screen shot:
After programming the "text after "IMPORTANT" is garbled in the first execution. (The "0.82.9.^.01" string is used to make sure the issue is in the build before I print the "IMPORTANT" string, normally, I would put the "PRINTF" statement given above right after basic initialization and before any messages are sent to the Tera Term console.
After that, I added the PRINTF statement given above before the "IMPORTANT" string PRINTF and the text comes out cleanly as you can see at the bottom of the screen shot.
You can avoid the need for this by doing a "Reset Terminal" (under the "Control" pull down in Tera Term) but this is an easy way to eliminate any action on your part.