I'm using the Delphi example to command my Create 2, I just adapted the demo code to Unicode (DelphiXE). I use the original iRobot USB to serial cable.
My Create 2 seemed to be responding fine to all the commands send via serial yesterday and correctly received all sensor data back this morning, until I recharged the battery. Now when I send "7" "Soft reset" the robot attempts every time to start a clean cycle. It also attempts to start the clean cycle when I press the clean button. It tells me to move the Roomba to a new location, which is normal in cleaning mode because my wheels are not touching my desk. Communication via serial seem to be fine because I still get the Soft Reset response texts in the log memo of my app when I use the 2 buttons method to soft reset my Create 2, so there is still communication both ways.
I must say I had the same yesterday after charging but after a while unexpectedly, don't know why, the robot responded again fine to my commands.
It really seems to me the Create 2 is stuck in the Cleaning mode, or am I missing something?
BTW, I also tried to fix the problem by removing the battery.