Hi Bala, > /opt/hardhat/devkit/ppc/405/bin/ppc_405-ld: ADDR uses undefined section ram Try changing this: > > __HEAP_START = ADDR(ram); > > __HEAP_END = ADDR(ram)+SIZEOF(ram); To this: __HEAP_START = __BSS_END; __HEAP_END = 0x204000; Cheers Nick