Added copy_data function to fix the global variable problems.

adc/adc.c

@@ -499,7 +499,7 @@ int32_t main(void)
 	ADC1->CR2 |= (1 << 3);
 	while((ADC1->CR2 & (1 << 3)));
 	ADC1->CR2 |= (1 << 2);
-	while((ADC1->CR2 & (1 << 2)));	
+	while((ADC1->CR2 & (1 << 2)));
 
 	// Start conversion with software trigger
 	ADC1->CR2 |= (1<<22);

mathtest/makefile

@@ -6,15 +6,24 @@ INCLUDES = -I.
 
 LINKER_SCRIPT = stm32.ld
 
-CFLAGS += -mcpu=cortex-m3 -mthumb
-CFLAGS += -O0
-CFLAGS += -fno-common -Wall
-CFLAGS += -ffunction-sections -fdata-sections -Wl,--gc-sections
-
-LDFLAGS += -march=armv7-m # Make sure to pull thumb libraries
+CFLAGS += -mcpu=cortex-m3 -mthumb # Processor setup
+CFLAGS += -O0 # Optimization is off
+CFLAGS += -g2 # Generate debug info
+CFLAGS += -fno-common
+CFLAGS += -Wall # Turn on warnings
+#CFLAGS += -pedantic # more warnings
+CFLAGS += -Wsign-compare
+CFLAGS += -mfloat-abi=soft -fsingle-precision-constant
+CFLAGS += -Wcast-align
+CFLAGS += -Wconversion # neg int const implicitly converted to uint
+CFLAGS += -fomit-frame-pointer # Do not use fp if not needed
+CFLAGS += -ffunction-sections -fdata-sections
+
+LDFLAGS += -march=armv7-m
 LDFLAGS += -nostartfiles
-LDFLAGS += -lm # link agains math
 LDFLAGS += --specs=nosys.specs
+LDFLAGS += -lm # link agains math
+LDFLAGS += -Wl,--gc-sections # Linker garbage collector
 LDFLAGS += -T$(LINKER_SCRIPT)
 
 CROSS_COMPILE = arm-none-eabi-
@@ -31,7 +40,7 @@ all: clean $(SRCS) build size
 build: $(TARGET).elf $(TARGET).hex $(TARGET).bin $(TARGET).lst
 
 $(TARGET).elf: $(OBJS)
-	$(CC) $(OBJS) $(LDFLAGS) -o $@
+	@$(CC) $(OBJS) $(LDFLAGS) -o $@
 
 %.o: %.c
 	@echo "Building" $<
@@ -71,4 +80,4 @@ clean:
 	@rm -f $(TARGET).lst
 	@rm -f $(TARGET).o
 
-.PHONY: all build size clean burn
+.PHONY: all build size clean burn debug

mathtest/mathtest.c

@@ -86,6 +86,7 @@ typedef struct
 } RCC_type;
 
 // Function declarations. Add your functions here
+void copy_data(void);
 int32_t main(void);
 
 /*************************************************
@@ -103,11 +104,46 @@ __attribute__ ((section(".vectors"))) = {
 	0,                              /* 0x00C HardFault                       */
 };
 
+/*************************************************
+* Copy the data contents from LMA to VMA
+*************************************************/
+void copy_data(void)
+{
+	extern char _etext, _sdata, _edata, _sbss, _ebss;
+	char *src = &_etext;
+	char *dst = &_sdata;
+
+	/* ROM has data at end of text; copy it.  */
+	while (dst < &_edata)
+		*dst++ = *src++;
+
+	/* Zero bss.  */
+	for (dst = &_sbss; dst< &_ebss; dst++)
+		*dst = 0;
+}
+
+double alpha;
+
+uint32_t glb_uint_array[80] = {
+	1 ,2 ,3 ,4 ,5 ,6 ,7 ,8 ,9 ,10,
+	11,12,13,14,15,16,17,18,19,20,
+	21,22,23,24,25,26,27,28,29,30,
+	31,32,33,34,35,36,37,38,39,40,
+	41,42,43,44,45,46,47,48,49,50,
+	51,52,53,54,55,56,57,58,59,60,
+	61,62,63,64,65,66,67,68,69,70,
+	71,72,73,74,75,76,77,78,79,80};
+
 /*************************************************
 * Main code starts from here
 *************************************************/
 int32_t main(void)
 {
+	// Copy LMA to VMA for data section
+	copy_data();
+
+	alpha = 0.5f;
+
 	uint32_t i, j;
 	// Enable GPIOD clock. Bit 5 in RCC APB2ENR register
 	RCC->APB2ENR |= (1 << 5);
@@ -119,9 +155,9 @@ int32_t main(void)
 
 	while(1)
 	{
-		for (i=1; i<0xFFFF; i++)
+		for (i=1; i<80; i++)
 		{
-			GPIOD->ODR = (uint16_t)sqrt((double)(i*i));
+			GPIOD->ODR = (uint16_t)sqrt((double)glb_uint_array[i] * alpha);
 			for (j=10000; j>0; j--); // Delay
 		}
 	}

mathtest/stm32.ld

@@ -6,25 +6,37 @@ MEMORY {
 }
 
 SECTIONS {
-	.text :
+	.text ORIGIN(rom) :
 	{
 		KEEP(*(.vectors))  /* Vector table */
 		*(.text*)          /* Program code */
 		*(.rodata*)        /* Read only data */
 		. = ALIGN(4);
-	} >rom
+		_etext = .;
+	}
 
-	.data :
+	_sidata = .;
+
+	.data ORIGIN(ram) :  AT ( ADDR (.text) + SIZEOF (.text) )
 	{
+		_sdata = .;
 		*(.data*)      /* Read-write initialized data */
 		. = ALIGN(4);
-	} >ram AT >rom
+		_edata = .;
+	}
+
 
-	.bss :
+	.bss ADDR (.data) + SIZEOF (.data):
 	{
+		_sbss = .;
 		. = ALIGN(4);
 		*(.bss*)       /* Read-write zero initialized data */
 		*(COMMON)
 		. = ALIGN(4);
-	} >ram
+		_ebss = .;
+	}
 }
+
+__text_size = SIZEOF (.text);
+__data_size = SIZEOF (.data);
+__bss_size  = SIZEOF (.bss);

pwm/makefile

@@ -7,14 +7,22 @@ INCLUDES = -I.
 LINKER_SCRIPT = stm32.ld
 
 CFLAGS += -mcpu=cortex-m3 -mthumb # Processor setup
-CFLAGS += -O0  # Optimization is off
-#CFLAGS += -g0  # Generate debug information
-CFLAGS += -fno-common -Wall
-CFLAGS += -ffunction-sections -fdata-sections -Wl,--gc-sections
+CFLAGS += -O0 # Optimization is off
+CFLAGS += -g2 # Generate debug info
+CFLAGS += -fno-common
+CFLAGS += -Wall # Turn on warnings
+#CFLAGS += -pedantic # more warnings
+CFLAGS += -Wsign-compare
+CFLAGS += -mfloat-abi=soft -fsingle-precision-constant
+CFLAGS += -Wcast-align
+#CFLAGS += -Wconversion # neg int const implicitly converted to uint
+CFLAGS += -fomit-frame-pointer # Do not use fp if not needed
+CFLAGS += -ffunction-sections -fdata-sections
 
 LDFLAGS += -march=armv7-m
 LDFLAGS += -nostartfiles
 LDFLAGS += --specs=nosys.specs
+LDFLAGS += -Wl,--gc-sections # Linker garbage collector
 LDFLAGS += -T$(LINKER_SCRIPT)
 
 CROSS_COMPILE = arm-none-eabi-
@@ -23,6 +31,7 @@ LD = $(CROSS_COMPILE)ld
 OBJDUMP = $(CROSS_COMPILE)objdump
 OBJCOPY = $(CROSS_COMPILE)objcopy
 SIZE = $(CROSS_COMPILE)size
+DBG = $(CROSS_COMPILE)gdb
 
 all: clean $(SRCS) build size
 	@echo "Successfully finished..."
@@ -55,6 +64,12 @@ size: $(TARGET).elf
 burn:
 	@st-flash write $(TARGET).bin 0x8000000
 
+debug:
+	@$(DBG) -tui --eval-command="target extended-remote :4242" \
+	--eval-command="layout asm" \
+	--eval-command="layout regs" \
+	 $(TARGET).elf
+
 clean:
 	@echo "Cleaning..."
 	@rm -f $(TARGET).elf
@@ -64,4 +79,4 @@ clean:
 	@rm -f $(TARGET).lst
 	@rm -f $(TARGET).o
 
-.PHONY: all build size clean burn
+.PHONY: all build size clean burn debug

pwm/pwm.c

@@ -248,6 +248,7 @@ typedef enum IRQn
 
 
 // Function declarations. Add your functions here
+void copy_data(void);
 void enable_interrupt(IRQn_type IRQn);
 void disable_interrupt(IRQn_type IRQn);
 void set_system_clock_to_25Mhz(void);
@@ -351,6 +352,24 @@ __attribute__ ((section(".vectors"))) = {
 	0,                              /* 74  USB OTG FS                      */
 };
 
+/*************************************************
+* Copy the data contents from LMA to VMA
+*************************************************/
+void copy_data(void)
+{
+	extern char _etext, _sdata, _edata, _sbss, _ebss;
+	char *src = &_etext;
+	char *dst = &_sdata;
+
+	/* ROM has data at end of text; copy it.  */
+	while (dst < &_edata)
+		*dst++ = *src++;
+
+	/* Zero bss.  */
+	for (dst = &_sbss; dst< &_ebss; dst++)
+		*dst = 0;
+}
+
 volatile uint32_t duty;
 volatile uint32_t period;
 
@@ -470,6 +489,9 @@ void tim1_handler(void)
 *************************************************/
 int32_t main(void)
 {
+	// Copy LMA to VMA for data section
+	copy_data();
+
 	duty = 1500;
 	period = 3000;
 	// Set clock to 72 MHz

pwm/stm32.ld

@@ -6,25 +6,37 @@ MEMORY {
 }
 
 SECTIONS {
-	.text :
+	.text ORIGIN(rom) :
 	{
 		KEEP(*(.vectors))  /* Vector table */
 		*(.text*)          /* Program code */
 		*(.rodata*)        /* Read only data */
 		. = ALIGN(4);
-	} >rom
+		_etext = .;
+	}
 
-	.data :
+	_sidata = .;
+
+	.data ORIGIN(ram) :  AT ( ADDR (.text) + SIZEOF (.text) )
 	{
+		_sdata = .;
 		*(.data*)      /* Read-write initialized data */
 		. = ALIGN(4);
-	} >ram AT >rom
+		_edata = .;
+	}
+
 
-	.bss :
+	.bss ADDR (.data) + SIZEOF (.data):
 	{
+		_sbss = .;
 		. = ALIGN(4);
 		*(.bss*)       /* Read-write zero initialized data */
 		*(COMMON)
 		. = ALIGN(4);
-	} >ram
+		_ebss = .;
+	}
 }
+
+__text_size = SIZEOF (.text);
+__data_size = SIZEOF (.data);
+__bss_size  = SIZEOF (.bss);