I put that in there for a reason. It may not happen all the time, but eventually you could blow up the processor.
Gerald On Thu, Mar 6, 2014 at 8:56 AM, Matthew Witherwax <ablec...@gmail.com>wrote: > As part of the Control of Mobile Robotics class offered through Cousera, > the students are building robots based around the BeagleBone Black. The > robot has 5 infrared distance sensors and 2 reflectance sensors used for > odometry. These sensors are connected via voltage dividers to pins 33, 35, > 36, 37, 38, 39, and 49 of P9, and are powered from the same power supply > used to power the BeagleBone Black. The System Manual has a rather > explicit warning: > > NOTE: DO NOT APPLY VOLTAGE TO ANY I/O PIN WHEN POWER IS NOT SUPPLIED TO > THE BOARD. IT WILL DAMAGE THE PROCESSOR AND VOID THE WARRANTY. > NO PINS ARE TO BE DRIVEN UNTIL AFTER THE SYS_RESET LINE GOES HIGH. > > My concern is the current arrangement would allow the sensors to begin > driving the pins before the SYS_RESET line goes high; however, I am a > software guy just starting down the hardware path. Thus far many in the > class have been using the robot without issue. Is my concern invalid? > > Thank you for your time. > > -- > For more options, visit http://beagleboard.org/discuss > --- > You received this message because you are subscribed to the Google Groups > "BeagleBoard" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to beagleboard+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/groups/opt_out. > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
