I purchased the BrickPi Advanced Power board with 12V power pack back at the end of January and have just gotten a chance to start experimenting with it.
I am having a problem with the board rebooting the Pi when one or two motors are switching direction with out stopping in between.
I have also implemented the program with both motors stopping before switching direction and the Pi continues to reboot when more than one motor is running.
Sometimes the Pi will reboot when only one motor is running ans switching directions even with stopping before switching directions.
I have tried using both the 12V power pack with fresh batteries as well as a power supply (wall wart variety, but of a higher quality) and experience the same problem.
I have tried running one motor on the A/B bank and one motor on the C/D bank with the same results.
Have not had a chance to put a scope on the power input from the expansion pins on the Pi board, but suspect that there may be a noise problem.
Attached is the python program I am using based on the test program for two motors posted by Jaikrishna.
At this point the Brick Pi board is useless to me if it will not drive at least two motors without rebooting the Pi and hate to think that I blew about $100 with my total purchase. So far the LEGO NXT switches and ultrasound sensor work just fine.
Here is the version information that I get when logging in via SSH with putty:
3.10.24+ #614 PREEMPT Thu Dec 19 20:38:42 GMT 2013 armv6l
I downloaded the latest image and created an SD card with it.