NV_PRAMDAC_CU_START_POS
NV_PRAMDAC_CU_START_POS,
uint32_t curpos = NVReadRAMDAC(dev, head, NV_PRAMDAC_CU_START_POS);
NVWriteRAMDAC(dev, head, NV_PRAMDAC_CU_START_POS, curpos);