微處理器 - Allwinner F1C100S (荔枝派Nano) - Assembly - LED

參考資料：
http://nano.lichee.pro/
https://mangopi.org/mangopi_r

電路圖


暫存器


配置功能


輸出控制


main.s

    .global _start
 
    .equ GPIO_BASE, 0x01c20800 
    .equ PE_CFG0,   (GPIO_BASE + (4 * 0x24) + 0x00)
    .equ PE_DATA,   (GPIO_BASE + (4 * 0x24) + 0x10)
  
    .arm
    .text
_start:
    .long 0xea000016
    .byte 'e', 'G', 'O', 'N', '.', 'B', 'T', '0'
    .long 0, __spl_size
    .byte 'S', 'P', 'L', 2
    .long 0, 0
    .long 0, 0, 0, 0, 0, 0, 0, 0
    .long 0, 0, 0, 0, 0, 0, 0, 0
  
_vector:
    b reset
    b .
    b .
    b .
    b .
    b .
    b .
    b .
    
reset:
    ldr r0, =PE_CFG0
    ldr r1, =0x00010000
    str r1, [r0]

    ldr r0, =PE_DATA
0:
    ldr r1, =0x10
    str r1, [r0]
    ldr r2, =50000
1:
    subs r2, #1
    bne 1b
    ldr r1, =0x00
    str r1, [r0]
    ldr r2, =50000
2:
    subs r2, #1
    bne 2b
    b 0b
    .end

main.ld

MEMORY {
    RAM : ORIGIN = 0, LENGTH = 32K
}

SECTIONS {
    text : {
        PROVIDE(__spl_start = .);
        *(.text*)
        PROVIDE(__spl_end = .);
    } > RAM
    PROVIDE(__spl_size = __spl_end - __spl_start);
}

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
	gcc mksunxi.c -o mksunxi
	./mksunxi main.bin

flash:
	sunxi-fel -p spiflash-write 0 main.bin

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

接著按住START按鍵，然後插入USB至電腦，可以找到如下裝置

$ lsusb
    Bus 002 Device 081: ID 1f3a:efe8 Onda (unverified) V972 tablet in flashing mode

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
    gcc mksunxi.c -o mksunxi
    ./mksunxi main.bin
    The bootloader head has been fixed, spl size is 512 bytes.

$ make flash
    sunxi-fel -p spiflash-write 0 main.bin
    100% [================================================]     1 kB,   55.9 kB/s

重新上電後，即可執行SPI Flash裡面的程式