Port function setting register 4
| P0 | Bit0 of PFR4 |
| P1 | Bit1 of PFR4 |
| P2 | Bit2 of PFR4 |
| P3 | Bit3 of PFR4 |
| P4 | Bit4 of PFR4 |
| P5 | Bit5 of PFR4 |
| P6 | Bit6 of PFR4 |
| P7 | Bit7 of PFR4 |
| P8 | Bit8 of PFR4 |
| P9 | Bit9 of PFR4 |
| PA | Bit10 of PFR4 |
| PB | Bit11 of PFR4 |
| PC | Bit12 of PFR4 |
| PD | Bit13 of PFR4 |
| PE | Bit14 of PFR4 |