Commands to the ARM-board and MPU9150

Hi, I'm a beginner that is experimenting with the MPU-9150 EVB and the ARM-board, but I have a couple of questions about the use of the MPU.

First, when I try to run de PC-demo provided by invensense, it the board seems to work fine. When I log, I see that the log frequency is 40Hz. Is this the same frequency used to run the "sword-algorithm"?

Second, when I give commands to the sensor through the ARM board (using Realterm) I get some unexpected behaviour. When I start up Realterm it states that the samplerate is somewhere between 40 and 80 hz (I guess that is configured by the Pc-demo application). Now I want to increase the sample rate to as high as possible, so I set "register 25 – SMPRT_DIV" by sending the command: WR681900 + CR (which should set SMPRT_DIV to 0). Now I see that the sample rate becomes around 320 Hz. So far so good, but when I try to set "Register 26 – CONFIG" by writing WR681A00 + CR (which should set the Gyroscope output rate to 8Khz) the output of the sensor stops... The weird thing is that when I givethe commands the other way around (first WR681A00 + CR and then WR681900 + CR), the sample rate goes to 520hz after the first command and again stops after the second. Is this a problem of the Realterm not being able to handle the sample rate? Or am I doing something wrong?

Third, after the sensor has stopped giving output (e.g. by giving the two previous commands) , I can only start up the stream again by starting up the PC-demo. I guess there are some settings done by the PC-Demo to start up, but I can´t figure out which ones... I tried the writing to the DEVICE_RESET bit in register 107, but no succes. Can you tell me which commands start up the device?

Lastly, when I start up RealTerm I see that the sensor is outputting: I1 + CR +LF. What is this data?

Hope this is clear enough!

Thanks in advance!