o Interrupt-driven serial port writing.

4 files changed, 289 insertions, 61 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index c894168..99b97dd 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -6,17 +6,17 @@ project(stm32f103-playground C CXX ASM)
 
 function(add_extra_commands target_name)
     add_custom_command(TARGET ${target_name} POST_BUILD
-            COMMAND arm-none-eabi-objdump -D ${target_name} > ${target_name}.asm)
+            COMMAND mkdir -p ${target_name}-info && arm-none-eabi-objdump -D ${target_name} > ${target_name}-info/${target_name}.asm)
     add_custom_command(TARGET ${target_name} POST_BUILD
-            COMMAND arm-none-eabi-nm ${target_name} > ${target_name}.nm)
+            COMMAND mkdir -p ${target_name}-info && arm-none-eabi-nm ${target_name} > ${target_name}-info/${target_name}.nm)
     add_custom_command(TARGET ${target_name} POST_BUILD
-            COMMAND arm-none-eabi-size ${target_name} > ${target_name}.size)
+            COMMAND mkdir -p ${target_name}-info && arm-none-eabi-size ${target_name} > ${target_name}-info/${target_name}.size)
     add_custom_command(TARGET ${target_name} POST_BUILD
-            COMMAND arm-none-eabi-readelf -a ${target_name} > ${target_name}.readelf)
+            COMMAND mkdir -p ${target_name}-info && arm-none-eabi-readelf -a ${target_name} > ${target_name}-info/${target_name}.readelf)
     add_custom_command(TARGET ${target_name} POST_BUILD
-            COMMAND arm-none-eabi-objcopy -O ihex ${target_name} ${target_name}.hex)
+            COMMAND mkdir -p ${target_name}-info && arm-none-eabi-objcopy -O ihex ${target_name} ${target_name}-info/${target_name}.hex)
     add_custom_command(TARGET ${target_name} POST_BUILD
-            COMMAND arm-none-eabi-objcopy -O binary ${target_name} ${target_name}.bin)
+            COMMAND mkdir -p ${target_name}-info && arm-none-eabi-objcopy -O binary ${target_name} ${target_name}-info/${target_name}.bin)
 endfunction()
 
 # https://github.com/cjlano/tinyprintf
@@ -78,7 +78,9 @@ add_executable(serial2.elf serial2.cpp init_low.s init_high.cpp include/stm32f10
         debug.cpp debug.h
         tmp/STM32F10x_StdPeriph_Lib_V3.5.0/Libraries/CMSIS/CM3/CoreSupport/core_cm3.c
         tmp/STM32F10x_StdPeriph_Lib_V3.5.0/Libraries/CMSIS/CM3/DeviceSupport/ST/STM32F10x/system_stm32f10x.c
+        tmp/STM32F10x_StdPeriph_Lib_V3.5.0/Libraries/STM32F10x_StdPeriph_Driver/src/misc.c
         tmp/STM32F10x_StdPeriph_Lib_V3.5.0/Libraries/STM32F10x_StdPeriph_Driver/src/stm32f10x_rcc.c
+        tmp/STM32F10x_StdPeriph_Lib_V3.5.0/Libraries/STM32F10x_StdPeriph_Driver/src/stm32f10x_usart.c
         tmp/STM32F10x_StdPeriph_Lib_V3.5.0/Libraries/STM32F10x_StdPeriph_Driver/src/stm32f10x_gpio.c
         )
 target_link_libraries(serial2.elf tinyprintf)
diff --git a/gdb-start b/gdb-start
index 07bb364..ead4d9b 100644
--- a/gdb-start
+++ b/gdb-start
@@ -27,7 +27,21 @@ define flash_serial1
     set confirm on
 
     monitor stm32f1x.cpu mwb 0x20000000 0x5a 20480
-    delete breakpoint 1
+    hbreak halt
+end
+
+define flash_serial2
+    shell cd build && make serial2.elf
+
+    monitor arm semihosting enable
+    monitor reset halt
+
+    set confirm off
+    file build/serial2.elf
+    load build/serial2.elf
+    set confirm on
+
+    monitor stm32f1x.cpu mwb 0x20000000 0x5a 20480
     hbreak halt
 end
 
diff --git a/init_low.s b/init_low.s
index bd7f329..1c3d10e 100644
--- a/init_low.s
+++ b/init_low.s
@@ -9,24 +9,68 @@ http://stackoverflow.com/questions/9565921/cortex-m3-initialisation
 
 .section .isr_vectors
 
+/* TODO: Move this to C code */
 .global vectors
 vectors:
-stacktop: .word 0x20001000
-.word _Reset_Handler
-.word NMI_Handler
-.word HardFault_Handler
-.word MemManage_Handler
-.word BusFault_Handler
-.word UsageFault_Handler
-.word halt
-.word halt
-.word halt
-.word halt
-.word halt
-.word halt
-.word halt
-.word halt
-.word halt
+    .word   0x20001000                      /* TODO: this should come from the linker */
+    .word   _Reset_Handler
+    .word   NMI_Handler
+    .word   HardFault_Handler
+    .word   MemManage_Handler
+    .word   BusFault_Handler
+    .word   UsageFault_Handler
+    .word   0                               /* Not used */
+    .word   0                               /* Not used */
+    .word   0                               /* Not used */
+    .word   0                               /* Not used */
+	.word	SVC_Handler
+	.word	DebugMon_Handler
+	.word	0                               /* Not used */
+	.word	PendSV_Handler
+	.word	SysTick_Handler
+	.word	WWDG_IRQHandler
+	.word	PVD_IRQHandler
+	.word	TAMPER_IRQHandler
+	.word	RTC_IRQHandler
+	.word	FLASH_IRQHandler
+	.word	RCC_IRQHandler
+	.word	EXTI0_IRQHandler
+	.word	EXTI1_IRQHandler
+	.word	EXTI2_IRQHandler
+	.word	EXTI3_IRQHandler
+	.word	EXTI4_IRQHandler
+	.word	DMA1_Channel1_IRQHandler
+	.word	DMA1_Channel2_IRQHandler
+	.word	DMA1_Channel3_IRQHandler
+	.word	DMA1_Channel4_IRQHandler
+	.word	DMA1_Channel5_IRQHandler
+	.word	DMA1_Channel6_IRQHandler
+	.word	DMA1_Channel7_IRQHandler
+	.word	ADC1_2_IRQHandler
+	.word	USB_HP_CAN1_TX_IRQHandler
+	.word	USB_LP_CAN1_RX0_IRQHandler
+	.word	CAN1_RX1_IRQHandler
+	.word	CAN1_SCE_IRQHandler
+	.word	EXTI9_5_IRQHandler
+	.word	TIM1_BRK_IRQHandler
+	.word	TIM1_UP_IRQHandler
+	.word	TIM1_TRG_COM_IRQHandler
+	.word	TIM1_CC_IRQHandler
+	.word	TIM2_IRQHandler
+	.word	TIM3_IRQHandler
+	.word	TIM4_IRQHandler
+	.word	I2C1_EV_IRQHandler
+	.word	I2C1_ER_IRQHandler
+	.word	I2C2_EV_IRQHandler
+	.word	I2C2_ER_IRQHandler
+	.word	SPI1_IRQHandler
+	.word	SPI2_IRQHandler
+	.word	USART1_IRQHandler
+	.word	USART2_IRQHandler
+	.word	USART3_IRQHandler
+	.word	EXTI15_10_IRQHandler
+	.word	RTCAlarm_IRQHandler
+	.word	USBWakeUp_IRQHandler
 
 /* VERY significant */
 .section .text
@@ -66,4 +110,150 @@ BusFault_Handler:
 UsageFault_Handler:
     b halt
 
+/*
+TODO: replace with functions like this:
+void TIM2_IRQHandler() __attribute__ ((weak, alias ("Default_Handler")));
+*/
+
+.weak SVC_Handler
+.thumb_set SVC_Handler, halt
+
+.weak DebugMon_Handler
+.thumb_set DebugMon_Handler, halt
+
+.weak PendSV_Handler
+.thumb_set PendSV_Handler, halt
+
+.weak SysTick_Handler
+.thumb_set SysTick_Handler, halt
+
+.weak WWDG_IRQHandler
+.thumb_set WWDG_IRQHandler, halt
+
+.weak PVD_IRQHandler
+.thumb_set PVD_IRQHandler, halt
+
+.weak TAMPER_IRQHandler
+.thumb_set TAMPER_IRQHandler, halt
+
+.weak RTC_IRQHandler
+.thumb_set RTC_IRQHandler, halt
+
+.weak FLASH_IRQHandler
+.thumb_set FLASH_IRQHandler, halt
+
+.weak RCC_IRQHandler
+.thumb_set RCC_IRQHandler, halt
+
+.weak EXTI0_IRQHandler
+.thumb_set EXTI0_IRQHandler, halt
+
+.weak EXTI1_IRQHandler
+.thumb_set EXTI1_IRQHandler, halt
+
+.weak EXTI2_IRQHandler
+.thumb_set EXTI2_IRQHandler, halt
+
+.weak EXTI3_IRQHandler
+.thumb_set EXTI3_IRQHandler, halt
+
+.weak EXTI4_IRQHandler
+.thumb_set EXTI4_IRQHandler, halt
+
+.weak DMA1_Channel1_IRQHandler
+.thumb_set DMA1_Channel1_IRQHandler, halt
+
+.weak DMA1_Channel2_IRQHandler
+.thumb_set DMA1_Channel2_IRQHandler, halt
+
+.weak DMA1_Channel3_IRQHandler
+.thumb_set DMA1_Channel3_IRQHandler, halt
+
+.weak DMA1_Channel4_IRQHandler
+.thumb_set DMA1_Channel4_IRQHandler, halt
+
+.weak DMA1_Channel5_IRQHandler
+.thumb_set DMA1_Channel5_IRQHandler, halt
+
+.weak DMA1_Channel6_IRQHandler
+.thumb_set DMA1_Channel6_IRQHandler, halt
+
+.weak DMA1_Channel7_IRQHandler
+.thumb_set DMA1_Channel7_IRQHandler, halt
+
+.weak ADC1_2_IRQHandler
+.thumb_set ADC1_2_IRQHandler, halt
+
+.weak USB_HP_CAN1_TX_IRQHandler
+.thumb_set USB_HP_CAN1_TX_IRQHandler, halt
+
+.weak USB_LP_CAN1_RX0_IRQHandler
+.thumb_set USB_LP_CAN1_RX0_IRQHandler, halt
+
+.weak CAN1_RX1_IRQHandler
+.thumb_set CAN1_RX1_IRQHandler, halt
+
+.weak CAN1_SCE_IRQHandler
+.thumb_set CAN1_SCE_IRQHandler, halt
+
+.weak EXTI9_5_IRQHandler
+.thumb_set EXTI9_5_IRQHandler, halt
+
+.weak TIM1_BRK_IRQHandler
+.thumb_set TIM1_BRK_IRQHandler, halt
+
+.weak TIM1_UP_IRQHandler
+.thumb_set TIM1_UP_IRQHandler, halt
+
+.weak TIM1_TRG_COM_IRQHandler
+.thumb_set TIM1_TRG_COM_IRQHandler, halt
+
+.weak TIM1_CC_IRQHandler
+.thumb_set TIM1_CC_IRQHandler, halt
+
+.weak TIM2_IRQHandler
+.thumb_set TIM2_IRQHandler, halt
+
+.weak TIM3_IRQHandler
+.thumb_set TIM3_IRQHandler, halt
+
+.weak TIM4_IRQHandler
+.thumb_set TIM4_IRQHandler, halt
+
+.weak I2C1_EV_IRQHandler
+.thumb_set I2C1_EV_IRQHandler, halt
+
+.weak I2C1_ER_IRQHandler
+.thumb_set I2C1_ER_IRQHandler, halt
+
+.weak I2C2_EV_IRQHandler
+.thumb_set I2C2_EV_IRQHandler, halt
+
+.weak I2C2_ER_IRQHandler
+.thumb_set I2C2_ER_IRQHandler, halt
+
+.weak SPI1_IRQHandler
+.thumb_set SPI1_IRQHandler, halt
+
+.weak SPI2_IRQHandler
+.thumb_set SPI2_IRQHandler, halt
+
+.weak USART1_IRQHandler
+.thumb_set USART1_IRQHandler, halt
+
+.weak USART2_IRQHandler
+.thumb_set USART2_IRQHandler, halt
+
+.weak USART3_IRQHandler
+.thumb_set USART3_IRQHandler, halt
+
+.weak EXTI15_10_IRQHandler
+.thumb_set EXTI15_10_IRQHandler, halt
+
+.weak RTCAlarm_IRQHandler
+.thumb_set RTCAlarm_IRQHandler, halt
+
+.weak USBWakeUp_IRQHandler
+.thumb_set USBWakeUp_IRQHandler, halt
+
 .end
diff --git a/serial2.cpp b/serial2.cpp
index 58ea536..c01aa13 100644
--- a/serial2.cpp
+++ b/serial2.cpp
@@ -1,22 +1,30 @@
-#include "tinyprintf.h"
 #include <stdint.h>
 #include <stm32f10x.h>
 #include <stm32f10x_rcc.h>
 #include <stm32f10x_gpio.h>
-#include <stddef.h>
-#include <stdarg.h>
-#include "tinyprintf.h"
+#include <stm32f10x_usart.h>
+#include <misc.h>
+
 #include "debug.h"
+#include "tinyprintf.h"
 
 int init_high();
 
 extern "C" void halt();
 
-#include "stm32f10x_conf.h"
-
 extern "C"
 __attribute__((naked))
 void HardFault_Handler_C(uint32_t *hardfault_args) {
+    dbg_printf("r0 = 0x%08x (%d)\n", hardfault_args[0], hardfault_args[0]);
+    dbg_printf("r1 = 0x%08x (%d)\n", hardfault_args[1], hardfault_args[1]);
+    dbg_printf("r2 = 0x%08x (%d)\n", hardfault_args[2], hardfault_args[2]);
+    dbg_printf("r3 = 0x%08x (%d)\n", hardfault_args[3], hardfault_args[3]);
+    dbg_printf("r12 = 0x%08x (%d)\n", hardfault_args[4], hardfault_args[4]);
+    dbg_printf("lr = 0x%08x (%d)\n", hardfault_args[5], hardfault_args[5]);
+    dbg_printf("pc = 0x%08x (%d)\n", hardfault_args[6], hardfault_args[6]);
+    dbg_printf("psr = 0x%08x (%d)\n", hardfault_args[7], hardfault_args[7]);
+    dbg_printf("\n");
+
     halt();
 }
 
@@ -30,6 +38,8 @@ int run = 1;
 
 volatile USART_TypeDef *usart1 = (volatile USART_TypeDef *) USART1_BASE;
 
+volatile uint8_t tx_ready = 0;
+
 /*
  * When we get there the stack pointer is set
  */
@@ -79,53 +89,65 @@ int main() {
     init.GPIO_Mode = GPIO_Mode_AF_PP;
     GPIO_Init(GPIOA, &init);
 
+    NVIC_PriorityGroupConfig(NVIC_PriorityGroup_0);
+    NVIC_InitTypeDef NVIC_InitStruct = {
+        /*.NVIC_IRQChannel =*/ USART1_IRQn,
+        /*.NVIC_IRQChannelPreemptionPriority =*/ 0,
+        /*.NVIC_IRQChannel =*/ 0,
+        /*.NVIC_IRQChannelCmd =*/ ENABLE,
+    };
+    NVIC_Init(&NVIC_InitStruct);
+    NVIC_EnableIRQ(USART1_IRQn);
+
     // 8 bit mode
     USART1->CR1 &= ~USART_CR1_M;
     USART1->CR2 &= ~USART_CR2_STOP_1;
 
-    USART1->CR1 |= USART_CR1_UE /* Set UART Enable */
-                   | USART_CR1_TE; /* Set Transmission Enable */
-
     // Set baud rate
     int mantissa = 39;
     int fraction = static_cast<int>(16 * 0.0625); // == 1
     // 72M / (16*39.0625) = 115200
     USART1->BRR = static_cast<uint16_t >(mantissa << 4 | fraction);
 
+    USART1->CR1 |= USART_CR1_UE /* Set UART Enable */
+                   | USART_CR1_TE /* Set Transmission Enable */
+                   | USART_CR1_TXEIE; /* Set TX buffer Empty Interrupt Enable */
+
     char c = 'A';
+    tx_ready = 1;
     while (run) {
-        int txe = USART1->SR & USART_SR_TXE;
-
-//        dbg_printf("1:%d?\n", x);
-
-//        char mm[100];
-//        tfp_sprintf(mm, "2:%d?\n", x);
-//        send_command(SYS_WRITE0, mm);
-
-//        printf(" %u?\n", usart1->SR);
-//        printf(" %u?\n", 1);
-
-        if (txe) {
-            GPIO_SetBits(GPIOB, GPIO_Pin_All);
-            GPIO_ResetBits(GPIOB, GPIO_Pin_All);
-
-            USART1->DR = (uint16_t) c;
-//            USART1->DR = 0x55;
-
-            if (c == 'Z') {
-                c = 'a';
-            } else if (c == 'z') {
-                c = '0';
-            } else if (c == '9') {
-                c = '\n';
-            } else if (c == '\n') {
-                c = 'A';
-            } else {
-                c++;
-            }
+        // wait for TX to be ready
+        while (!tx_ready);
+        tx_ready = 0;
+
+        GPIO_SetBits(GPIOB, GPIO_Pin_All);
+        GPIO_ResetBits(GPIOB, GPIO_Pin_All);
+
+        USART1->DR = (uint16_t) c;
+        USART_ITConfig(USART1, USART_IT_TXE, ENABLE);
+
+        if (c == 'Z') {
+            c = 'a';
+        } else if (c == 'z') {
+            c = '0';
+        } else if (c == '9') {
+            c = '\n';
+        } else if (c == '\n') {
+            c = 'A';
+        } else {
+            c++;
         }
     }
 
     return 0;
 }
 
+extern "C"
+void USART1_IRQHandler() {
+    tx_ready = 1;
+
+    if (USART_GetITStatus(USART1, USART_IT_TXE) == SET) {
+        // Disable the interrupt
+        USART_ITConfig(USART1, USART_IT_TXE, DISABLE);
+    }
+}