BKTR_MEM_DMA_PROG
bktr->dma_prog = bktr_retrieve_address(unit, BKTR_MEM_DMA_PROG);
bktr_store_address(unit, BKTR_MEM_DMA_PROG, bktr->dma_prog);
case BKTR_MEM_DMA_PROG: memory_list[unit].dma_prog = addr;
case BKTR_MEM_DMA_PROG: return memory_list[unit].dma_prog;