掌機 - Miyoo Flip - Assembly - LED

綠色LED是連接到GPIO0-12腳位，GPIO0的映射位址如下：


Register


Data-Low


Data-High


Direction Low and High


main.s

    .equ GPIO0_BASE, 0xFDD60000
    .equ GPIO1_BASE, 0xFE740000
    .equ GPIO2_BASE, 0xFE750000
    .equ GPIO3_BASE, 0xFE760000
    .equ GPIO4_BASE, 0xFE770000

    .global	_start
_start:
    b reset

reset:
    ldr x0, =GPIO0_BASE
    ldr w1, =0xffffffff
    str w1, [x0, #8]
    str w1, [x0, #12]

    ldr w1, =(1 << 12)
    ldr w2, =0xffff0000
0:
    eor w2, w2, w1
    orr w2, w2, #2
    str w2, [x0, #0]
    ldr x5, =0x3ffffff
1:
    subs x5, x5, #1
    bne 1b
    b 0b
    .end

main.ld

MEMORY {
    RAM : ORIGIN = 0, LENGTH = 64K
}

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

Makefile

all:
	aarch64-linux-gnu-as -mcpu=cortex-a53 -o main.o main.s
	aarch64-linux-gnu-ld -T main.ld -o main.elf main.o
	aarch64-linux-gnu-objcopy -O binary main.elf main.bin

run:
	xrock extra maskrom --rc4 off --sram main.bin

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

接著讓Miyoo Flip進入MASKROM模式後，執行如下命令：

$ make
    arch64-linux-gnu-as -mcpu=cortex-a53 -o main.o main.s
    aarch64-linux-gnu-ld -T main.ld -o main.elf main.o
    aarch64-linux-gnu-objcopy -O binary main.elf main.bin

$ make run
    xrock extra maskrom --rc4 off --sram main.bin

完成