Add firmware wireframe

src/startup.S

@@ -0,0 +1,172 @@
+.syntax unified
+.thumb
+
+.global Reset_Handler
+.type Reset_Handler, %function
+Reset_Handler:
+
+init_data:
+    ldr r2, =_start_init_data
+    ldr r3, =_start_data
+    ldr r1, =_end_data
+
+init_data_loop:
+    cmp r3, r1
+    bhs zero_bss
+    ldr r0, [r2]
+    str r0, [r3]
+    adds r2, r2, #4
+    adds r3, r3, #4
+    b init_data_loop
+
+zero_bss:
+    ldr r3, =_start_bss
+    ldr r1, =_end_bss
+    movs r0, #0
+
+zero_bss_loop:
+    cmp r3, r1
+    bhs init_finished
+    str r0, [r3]
+    adds r3, r3, #4
+    b zero_bss_loop
+
+init_finished:
+    bl SystemInit
+    bl __libc_init_array
+    bl main
+
+infinite_loop:
+    b infinite_loop
+
+.size Reset_Handler, .-Reset_Handler
+
+.section .vectors, "a"
+.word _end_stack
+.word Reset_Handler
+.word NMI_Handler
+.word HardFault_Handler
+.word 0
+.word 0
+.word 0
+.word 0
+.word 0
+.word 0
+.word 0
+.word SVC_Handler
+.word 0
+.word 0
+.word PendSV_Handler
+.word SysTick_Handler
+.word WWDG_IRQHandler
+.word 0
+.word RTC_IRQHandler
+.word FLASH_IRQHandler
+.word RCC_IRQHandler
+.word EXTI0_1_IRQHandler
+.word EXTI2_3_IRQHandler
+.word EXTI4_15_IRQHandler
+.word 0
+.word DMA1_Channel1_IRQHandler
+.word DMA1_Channel2_3_IRQHandler
+.word DMA1_Channel4_5_IRQHandler
+.word ADC1_IRQHandler
+.word TIM1_BRK_UP_TRG_COM_IRQHandler
+.word TIM1_CC_IRQHandler
+.word 0
+.word TIM3_IRQHandler
+.word 0
+.word 0
+.word TIM14_IRQHandler
+.word 0
+.word TIM16_IRQHandler
+.word TIM17_IRQHandler
+.word I2C1_IRQHandler
+.word 0
+.word SPI1_IRQHandler
+.word 0
+.word USART1_IRQHandler
+.word 0
+.word 0
+.word 0
+.word 0
+
+.type Dummy_Handler, %function
+Dummy_Handler:
+    b Dummy_Handler
+
+.weak NMI_Handler
+.thumb_set NMI_Handler, Dummy_Handler
+
+.weak HardFault_Handler
+.thumb_set HardFault_Handler, Dummy_Handler
+
+.weak SVC_Handler
+.thumb_set SVC_Handler, Dummy_Handler
+
+.weak PendSV_Handler
+.thumb_set PendSV_Handler, Dummy_Handler
+
+.weak SysTick_Handler
+.thumb_set SysTick_Handler, Dummy_Handler
+
+.weak WWDG_IRQHandler
+.thumb_set WWDG_IRQHandler, Dummy_Handler
+
+.weak RTC_IRQHandler
+.thumb_set RTC_IRQHandler, Dummy_Handler
+
+.weak FLASH_IRQHandler
+.thumb_set FLASH_IRQHandler, Dummy_Handler
+
+.weak RCC_IRQHandler
+.thumb_set RCC_IRQHandler, Dummy_Handler
+
+.weak EXTI0_1_IRQHandler
+.thumb_set EXTI0_1_IRQHandler, Dummy_Handler
+
+.weak EXTI2_3_IRQHandler
+.thumb_set EXTI2_3_IRQHandler, Dummy_Handler
+
+.weak EXTI4_15_IRQHandler
+.thumb_set EXTI4_15_IRQHandler, Dummy_Handler
+
+.weak DMA1_Channel1_IRQHandler
+.thumb_set DMA1_Channel1_IRQHandler, Dummy_Handler
+
+.weak DMA1_Channel2_3_IRQHandler
+.thumb_set DMA1_Channel2_3_IRQHandler, Dummy_Handler
+
+.weak DMA1_Channel4_5_IRQHandler
+.thumb_set DMA1_Channel4_5_IRQHandler, Dummy_Handler
+
+.weak ADC1_IRQHandler
+.thumb_set ADC1_IRQHandler, Dummy_Handler
+
+.weak TIM1_BRK_UP_TRG_COM_IRQHandler
+.thumb_set TIM1_BRK_UP_TRG_COM_IRQHandler, Dummy_Handler
+
+.weak TIM1_CC_IRQHandler
+.thumb_set TIM1_CC_IRQHandler, Dummy_Handler
+
+.weak TIM3_IRQHandler
+.thumb_set TIM3_IRQHandler, Dummy_Handler
+
+.weak TIM14_IRQHandler
+.thumb_set TIM14_IRQHandler, Dummy_Handler
+
+.weak TIM16_IRQHandler
+.thumb_set TIM16_IRQHandler, Dummy_Handler
+
+.weak TIM17_IRQHandler
+.thumb_set TIM17_IRQHandler, Dummy_Handler
+
+.weak I2C1_IRQHandler
+.thumb_set I2C1_IRQHandler, Dummy_Handler
+
+.weak SPI1_IRQHandler
+.thumb_set SPI1_IRQHandler, Dummy_Handler
+
+.weak USART1_IRQHandler
+.thumb_set USART1_IRQHandler, Dummy_Handler
+