HI EVERYBODY OUT THERE!!!!!
just to ask, i'm using another motherboard of Robotis Open CM 9.04, with an RTC DS1307. i'm not sure if it works together. because it works on an arduino uno.
any idea guys?):
DS1307 is intended for 5V logic wheter most arm processors are 3,3V. But logic levels on the DS130 are specified to low=-0,5V..0.8V and high = 2,2...Vcc(5v)+0.3. So it is might be possible to connect the DS1307 to the controller and have communication going. But you still need a 5V supply for the DS1307 since the supply voltage determines whether the chip is online or not. DS1337 would be a better alternative, or google for 3.3V rtc