src.c += (
    "16x50_base.c",
    "16x50_pmio.c",
    "16x50_mmio.c",
    "16x50_dev.c",
)

if config.xt_16x50:
    src.c += "16x50_isa.c"

if config.pci_16x50:
    src.c += "16x50_pci.c"