I have tried to write port A,B and C in the MCU by the following code which supposed to be correct. However, the port are not set to be 0. Does anybody know why? PORTCCFG= 0x00; OEC =0xFF; OUTC=0x00; PORTBCFG= 0x00; OEB =0xFF; OUTB=0x00; PORTACFG= 0x00; OEA =0xFF; OUTA=0x00;