微處理器 - Microchip ATSAMD21G18 (Seeed Studio XIAO SAMD21) - Assembly - LED

參考資訊：
https://github.com/dwelch67/atsamd_samples
https://cdn.sparkfun.com/datasheets/Dev/Arduino/Boards/Atmel-42181-SAM-D21_Datasheet.pdf

LED腳位(PA-17)


暫存器


配置方式


main.s

    .cpu cortex-m0
    .thumb

    .equiv PORT_BASE, 0x41004400
    .equiv PORT_A,    0x00
    .equiv PORT_DIR,  0x00
    .equiv PORT_OUT,  0x10

    .thumb_func
    .global _start
_start:
    .word 0x20001000
    .word reset
    .word hang
    .word hang
    .word hang
    .word hang
    .word hang
    .word hang
    .word hang
    .word hang
    .word hang
    .word hang
    .word hang
    .word hang
    .word hang
    .word hang
 
    .thumb_func
reset:
    ldr r0, =PORT_BASE
    ldr r1, =(1 << 17)
    str r1, [r0, #(PORT_A + PORT_DIR)]

    ldr r2, =(1 << 17)
0:
    eor r1, r2
    str r1, [r0, #(PORT_A + PORT_OUT)]
    ldr r3, =100000
1:
    sub r3, #1
    cmp r3, #0
    bne 1b
    b 0b
 
    .thumb_func
hang:
    b .
    .end

main.ld

MEMORY {
    RAM : ORIGIN = 0x00000000, LENGTH = 0x1000
}

SECTIONS {
    .text : { *(.text*) } > RAM
    .rodata : { *(.rodata*) } > RAM
    .bss : { *(.bss*) } > RAM
}

Makefile

all:
	arm-none-eabi-as -mcpu=cortex-m0 -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

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

編譯

$ make
    arm-none-eabi-as -mcpu=cortex-m0 -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

開發板連接SWD後，開啟J-Flash


選擇ATSAMD21G18


SWD 4000khz


Connect


連線成功


Ctrl+O載入main.bin，起始位址0x00


載入main.bin後


燒錄


燒錄完成


執行


執行狀態


完成