嵌入式学习：裸机开发_L5_BSP工程管理LED实验

0. 本节目标

• Makefile的编写：函数使用
• BSP分门别类

1. 目录结构

2. 硬件层电路

2.1 正点原子 i.MX6ULL ALPHA V2.2 开发板

查看底板原理图可知：

功能管脚	芯片引脚
LED0	GPIO1_IO03

2.2 飞凌i.MX6UL-C开发板

3. 软件编写

Makefile

CROSS_COMPILE       ?= arm-linux-gnueabihf-
TARGET              ?= ledc

CC                  := $(CROSS_COMPILE)gcc
LD                  := $(CROSS_COMPILE)ld
OBJCOPY             := $(CROSS_COMPILE)objcopy
OBJDUMP             := $(CROSS_COMPILE)objdump

INCUDIRS			:= 	imx6ull \
						bsp/clk	\
						bsp/led	\
						bsp/delay

SRCDIRS				:=	project	\
						bsp/clk	\
						bsp/led	\
						bsp/delay

INCLUDE 			:=	$(patsubst %, -I %, $(INCUDIRS))

SFILES				:=	$(foreach dir, $(SRCDIRS), $(wildcard $(dir)/*.S))
CFILES				:=	$(foreach dir, $(SRCDIRS), $(wildcard $(dir)/*.c))

SFILENDIR			:=	$(notdir $(SFILES))
CFILENDIR			:=	$(notdir $(CFILES))

SOBJS				:=	$(patsubst %, obj/%, $(SFILENDIR:.S=.o))
COBJS				:=	$(patsubst %, obj/%, $(CFILENDIR:.c=.o))

OBJS				:=	$(SOBJS)$(COBJS)

VPATH				:=	$(SRCDIRS)

.PHONY: clean

$(TARGET).bin : $(OBJS)
	$(LD) -Timx6ull.lds -o $(TARGET).elf $^
	$(OBJCOPY) -O binary -S $(TARGET).elf $@
	$(OBJDUMP) -D -m arm $(TARGET).elf > $(TARGET).dis

$(SOBJS) : obj/%.o : %.S
	$(CC) -Wall -nostdlib -c -O2 $(INCLUDE) -o $@ $<

$(COBJS) : obj/%.o : %.c
	$(CC) -Wall -nostdlib -c -O2 $(INCLUDE) -o $@ $<

clean:
	rm -rf $(TARGET).elf $(TARGET).bin $(TARGET).dis $(OBJS)

print:
	@echo INCLUDE = $(INCLUDE)
	@echo SFILES = $(SFILES)
	@echo CFILES = $(CFILES)
	@echo SFILENDIR = $(SFILENDIR)
	@echo CFILENDIR = $(CFILENDIR)
	@echo SOBJS = $(SOBJS)
	@echo COBJS = $(COBJS)
	@echo OBJS = $(OBJS)

$(NAME).bin : $(OBJS)
	$(LD) -Timx6ull.lds -o $(NAME).elf $^
	$(OBJCOPY) -O binary -S $(NAME).elf $@
	$(OBJDUMP) -D -m arm $(NAME).elf > $(NAME).dis

%.o : %.c
	$(CC) -Wall -nostdlib -c -O2 -o $@ $<

%.o : %.S
	$(CC) -Wall -nostdlib -c -O2 -o $@ $<