MEMORY {
	rom : ORIGIN = 0x00000000, LENGTH = 0x00008000
	sram : ORIGIN = 0x10000000, LENGTH = 0x00001000
	main_ram : ORIGIN = 0x40000000, LENGTH = 0x04000000
	spiflash : ORIGIN = 0x20000000, LENGTH = 0x00200000
}