Erik, thanks for answering:
What about this configuration?
Is there something missing?

Thanks
// channel 0
P0M1 |= 0x02;
P0M2 &= ~0x02;
// channel 1
P0M1 |= 0x04;
P0M2 &= ~0x04;
// channel 2
P0M1 |= 0x08;
P0M2 &= ~0x08;
// channel 3
P0M1 |= 0x10;
P0M2 &= ~0x10;