Catalyzes the oxidation of either pyridoxine 5'-phosphate (PNP) or pyridoxamine 5'-phosphate (PMP) into pyridoxal 5'-phosphate (PLP). {ECO:0000269|PubMed:12824491, ECO:0000269|PubMed:15182361, ECO:0000269|PubMed:15772097}. This is the function of PNPO (pyridoxamine 5'-phosphate oxidase, Ensembl gene identifier ENSG00000108439).