掌機 - Game & Watch: The Legend of Zelda - Assembly - LED

參考資訊：
https://github.com/ghidraninja/game-and-watch-backup
https://www.st.com/resource/en/datasheet/stm32h7b0vb.pdf
https://www.st.com/resource/en/reference_manual/dm00463927-stm32h7a37b3-and-stm32h7b0-value-line-advanced-armbased-32bit-mcus-stmicroelectronics.pdf

LED腳位(PE-11)


PORTE Clock


Mode


Output


main.s

    .equiv PORTE_BASE,  0x58021000
    .equiv GPIO_MODER,  0x0000
    .equiv GPIO_ODR,    0x0014

    .equiv RCC_BASE,    0x58024400
    .equiv RCC_AHB4ENR, 0x0140

    .thumb
    .cpu cortex-m7
    .syntax unified

    .global _start

    .text
    .org 0x0000
_start:
    .word 0x20020000
    .word reset

    .org 0x0100
    .thumb_func
reset:
    ldr r0, =RCC_BASE
    ldr r1, [r0, #RCC_AHB4ENR]
    orr r1, #(1 << 4)
    str r1, [r0, #RCC_AHB4ENR]

    ldr r0, =PORTE_BASE
    ldr r1, =(1 << 22)
    str r1, [r0, #GPIO_MODER]
    ldr r1, =(0 << 11)
    str r1, [r0, #GPIO_ODR]

0:
    eor r1, #(1 << 11)
    str r1, [r0, #GPIO_ODR]
    ldr r2, =0x2000000
1:
    subs r2, #1
    bne 1b
    b 0b
    .end

main.ld

MEMORY {
    ITCMRAM  (xrw) : ORIGIN = 0x00000000, LENGTH = 64K
    DTCMRAM  (xrw) : ORIGIN = 0x20000000, LENGTH = 128K
    RAM      (xrw) : ORIGIN = 0x24000000, LENGTH = 1024K
    FLASH    (xr ) : ORIGIN = 0x08000000, LENGTH = 128K
    EXTFLASH (xr ) : ORIGIN = 0x90000000, LENGTH = 1024K
}

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

main.cfg

source [find interface/stlink.cfg]
adapter speed 500
transport select hla_swd
source [find target/stm32h7x.cfg]
reset_config none

Makefile

all:
	arm-none-eabi-as -mcpu=cortex-m7 main.s -o main.o
	arm-none-eabi-ld -T main.ld -o main.elf main.o

flash:
	openocd -f main.cfg -c "init; halt; program main.elf; reset; exit;"

clean:
	rm -rf main.o main.elf

編譯、燒錄

$ make
    arm-none-eabi-as -mcpu=cortex-m7 main.s -o main.o
    arm-none-eabi-ld -T main.ld -o main.elf main.o

$ make flash
    openocd -f main.cfg -c "init; halt; program main.elf; reset; exit;"
    Open On-Chip Debugger 0.11.0-rc1+dev-00010-gc69b4deae-dirty (2020-12-27-01:20)
    Licensed under GNU GPL v2
    For bug reports, read
      http://openocd.org/doc/doxygen/bugs.html
    Info : The selected transport took over low-level target control. The results might differ compared to plain JTAG/SWD
    none separate

    Info : clock speed 1800 kHz
    Info : STLINK V2J17S4 (API v2) VID:PID 0483:3748
    Info : Target voltage: 3.202613
    Info : stm32h7x.cpu0: hardware has 8 breakpoints, 4 watchpoints
    Info : starting gdb server for stm32h7x.cpu0 on 3333
    Info : Listening on port 3333 for gdb connections
    target halted due to debug-request, current mode: Thread 
    xPSR: 0x21000000 pc: 0x08000126 msp: 0x20020000
    target halted due to debug-request, current mode: Thread 
    xPSR: 0x01000000 pc: 0x08000100 msp: 0x20020000
    ** Programming Started **
    Info : Device: STM32H7Ax/7Bx
    Info : STM32H7 flash has dual banks
    Info : Bank (0) size is 1024 kb, base address is 0x08000000
    Info : Padding image section 0 at 0x08000134 with 12 bytes (bank write end alignment)
    Warn : Adding extra erase range, 0x08000140 .. 0x08001fff
    ** Programming Finished **

完成