微處理器 - Nuvoton NUC972 - Assembly - LED

參考資訊：
https://github.com/OpenNuvoton/NUC970_NonOS_BSP

Enable GPIO Clock


GPIO Direction


Output Data


main.s

    .equ GPIOB_DIR,     (0xb8003000 + 0x40)
    .equ GPIOB_DATAOUT, (0xb8003000 + 0x44)
    .equ CLK_PCLKEN0,   (0xb0000200 + 0x18)
 
    .text
    .align 2
    .global _start
_start:    b reset
_undef:    b .
_swi:      b .
_pabort:   b .
_dabort:   b .
_reserved: b .
_irq:      b .
_fiq:      b .
 
reset:
    ldr r0, =CLK_PCLKEN0
    ldr r1, [r0]
    orr r1, #(1 << 3)
    str r1, [r0]
 
    ldr r0, =GPIOB_DIR
    ldr r1, =(1 << 0)
    str r1, [r0]
loop:
    ldr r0, =GPIOB_DATAOUT
    ldr r1, =(1 << 0)
    str r1, [r0]
    ldr r4, =500000
1:
    nop
    subs r4, r4, #1
    bne 1b
    ldr r0, =GPIOB_DATAOUT
    ldr r1, =~(1 << 0)
    str r1, [r0]
    ldr r4, =500000
1:
    nop
    subs r4, r4, #1
    bne 1b
    b loop
    .end

main.ld

MEMORY {
    RAM(rwx) : ORIGIN = 0x000000, LENGTH = 0x08000000
}

SECTIONS {
    .text : {
        *(.text);
    } > RAM
}

Makefile

all:
	arm-none-eabi-as -mcpu=arm9 -o main.o main.s
	arm-none-eabi-ld -T main.ld -o main.elf main.o
	arm-none-eabi-objcopy -O binary main.elf main.bin

flash:
	sudo nuwriter -m sdram -d NUC972DF62Y.ini -a 0 -w main.bin -n

clean:
	rm -rf main.o main.elf main.bin

編譯、燒錄

$ make
    arm-none-eabi-as -mcpu=arm9 -o main.o main.s
    arm-none-eabi-ld -T main.ld -o main.elf main.o
    arm-none-eabi-objcopy -O binary main.elf main.bin

$ make flash
    sudo nuwriter -m sdram -d NUC972DF62Y.ini -a 0 -w main.bin -n

完成