USART receive interrupt stm32 - c

I develop on a map I'm working on STM32 and USART interrupts. After configuring the USART1 and make Enable receive interrupt. The problem that the interruption of reception have no detected????

Such a question is difficult to answer without knowing which specific processor you are using, which board you are using, and/or which compiler you are using. But in an attempt to be helpful, here's my code.
Here's my GPIO and NVIC initialization code using Sourcery CodeBench Lite with an STM32F4 processor mounted on a custom board.
GPIO_InitTypeDef GPIO_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);
RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART3, ENABLE);
GPIO_PinAFConfig(GPIOB, GPIO_PinSource10, GPIO_AF_USART3);
GPIO_PinAFConfig(GPIOB, GPIO_PinSource11, GPIO_AF_USART3);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10 | GPIO_Pin_11;
GPIO_Init(GPIOB, &GPIO_InitStructure);
// Enable the USART RX Interrupt
USART_ITConfig(USART3, USART_IT_RXNE, ENABLE);
NVIC_InitStructure.NVIC_IRQChannel = USART3_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
Of course your settings will vary depending on your processor, board and interrupt priority.
Here's my interrupt handler code. In my development environment, this handler is declared in my startup assembly file as a weak reference to Default_Handler...
Default_Handler:
b .
/* ... */
.word USART3_IRQHandler
/* ... */
.weak USART3_IRQHandler
.thumb_set USART3_IRQHandler,Default_Handler
... so as long as I provide a new declaration and implementation of this interrupt handler, the weak reference will be replaced. Here's what my code looks like.
//Interrupt handler declaration
void USART3_IRQHandler();
If you are using C++ you will need to declare it as follows:
//Interrupt handler declaration in C/C++
#ifdef __cplusplus
extern "C" {
#endif
void USART3_IRQHandler();
#ifdef __cplusplus
}
#endif
And here's the interrupt handler implemenation.
//Interrupt handler implementation
void USART3_IRQHandler()
{
//handle interrupt
}

Here's short and simple code to configure STM32 USART (USART3) and Interrupt Handler.
Configure and Init
void Init_USART3()
{
// PB.11 = RX Floating Input
// PB.10 = TX Alternate function output Push-pull 50 MHz
RCC->APB2ENR = RCC->APB2ENR | (RCC_APB2ENR_IOPBEN);
RCC->APB1ENR |= RCC_APB1ENR_USART3EN; // enable clock for USART3.
GPIOB->CRH = GPIOB->CRH & 0xFFFF00FF;
GPIOB->CRH = GPIOB->CRH | 0x00004B00;
USART3->BRR =72000000/9600; // set baudrate.
USART3->CR1 |= (USART_CR1_RE | USART_CR1_TE); // RX, TX enable.
USART3->CR1 |= USART_CR1_UE; // USART3 enable.
USART3->CR1 |= USART_CR1_RXNEIE; // UART3 Receive Interrupt Enable.
// Enable interrupt fromUSART1(NVIC level)
NVIC_EnableIRQ(USART3_IRQn);
}
Handle Receive Interrupt
void USART3_IRQHandler()
{
if(USART3->SR & USART_SR_RXNE)
{
// Do Something
}
}

Make sure you don't call HAL_UART_Transmit() on the same usart that you try interrupt. It is because this function calls UART_WaitOnFlagUntilTimeout() which disables the interrupt. The trace printf() that user7404301 mentioned above most likely calls it.

SAMPLE CODING TO HANDLE RECEIVE INTERRUPT
//USART1 Interrupt Handler
void USART1_IRQHandler(void)
{
if(USART_GetITStatus(USART1, USART_IT_RXNE) != RESET)//enter interrupt when STM32 receice data.
{
USART_ClearITPendingBit(USART1, USART_IT_RXNE);
USART_Temp_Data = (unsigned char) USART_ReceiveData(USART1); //receive a char
}
}

I had the same question with Eclipse(GCC)before and finally I found out the problem.The problem is not at the code but the "trace_printf", if you are using this API to print any details while running, the "trace_printf" will break the uart and your receive interrupt will never ocurrs.So, have a try, not use it and set breakpoints to see what you have recveived.

Related

STM32F407 USART1 : Clearing USART_FLAG_TC requires pgm to be halted before actually clearing the bit

When initializing USART1 on STM32F407 I have run into a problem when enabling TC interrupt. The TC flag in SR is set ('1') as soon as the USART RCC is enabled and clearing the flag before enabling TC interrupt has become a headache for me because it throws a TC interrupt as soon as UART_IT_TC is enabld. i.e. this is a startup problem.
By writing 0 to the flag in status register (SR) when initializing the USART and before enabling interrupts should clear the flags. But it does not when I run the program straight trough, but (!!!) if having a breakpoint and stepping trough the code where SR is cleared works fine, TC flag is set to 0.
Therefor i always get a TC interrupt even before transmitting anything if I run the code without a breakpoint. And then another one after transmitting a character, naturally. But when I was using a breakpoint where TC flag is cleared gives only one TC IRQ and thats when actually transmitting something.
Inside the IRQ handler I also clear the flags by writing 0 to SR register and this works without any breakpoint. Both transmitting and receiving data works well after this.
So, timing issue was in my mind, but adding even an second delay did not change behavior and then it should not work clearing the SR register later either. Or? Does USARTs require settling time for RCC before initializing the USART?
void Console_init(long baud)
{
GPIO_InitTypeDef GPIO_InitStruct;
USART_InitTypeDef USART_InitStruct;
NVIC_InitTypeDef NVIC_InitStruct;
/* Init clock domains */
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);
/* Set alternate functions */
GPIO_PinAFConfig(GPIOA, GPIO_PinSource9, GPIO_AF_USART1);
GPIO_PinAFConfig(GPIOA, GPIO_PinSource10, GPIO_AF_USART1);
/* Init GPIO pins */
GPIO_StructInit(&GPIO_InitStruct);
GPIO_InitStruct.GPIO_Pin = GPIO_Pin_9 | GPIO_Pin_10;
GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStruct.GPIO_OType = GPIO_OType_PP;
GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_UP;
GPIO_InitStruct.GPIO_Speed = GPIO_Speed_25MHz;
GPIO_Init(GPIOA, &GPIO_InitStruct);
/* Configure UART setup */
USART_StructInit(&USART_InitStruct);
USART_InitStruct.USART_BaudRate = baud;
USART_InitStruct.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
USART_InitStruct.USART_Mode = USART_Mode_Tx | USART_Mode_Rx;
USART_InitStruct.USART_Parity = USART_Parity_No;
USART_InitStruct.USART_StopBits = USART_StopBits_1;
USART_InitStruct.USART_WordLength = USART_WordLength_8b;
USART_Init(USART1, &USART_InitStruct);
/* Enable global interrupts for USART */
NVIC_InitStruct.NVIC_IRQChannel = USART1_IRQn;
NVIC_InitStruct.NVIC_IRQChannelCmd = ENABLE;
NVIC_InitStruct.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStruct.NVIC_IRQChannelSubPriority = 1;
NVIC_Init(&NVIC_InitStruct);
/* Clear old interrupt flags and enable required IRQs*/
USART1->SR = 0;
/* Enable USART */
USART_Cmd(USART1, ENABLE);
}
void console_transmit(void)
{
USART_ITConfig(USART1, USART_IT_TC, ENABLE);
USART1->DR = 0x55;
}
void USART1_IRQHandler(void)
{
if (USART1->SR & USART_FLAG_TC)
{
USART_ITConfig(USART1, USART_IT_TC, DISABLE);
}
USART1->SR = 0;
}
In this code I will get two interrupts on TC, one as soon I enables TC and one after character is transmitted. This code is what I am using now while trying to understand the issue.
Note: I have also tried to clear the SR inside console_transmit before enabling TC but to no help. It almost like it requires to be cleared inside the interrupt handler.
I think this is a conceptual misunderstanding.
A transmit interrupt does not tell you that something has been transmitted. It tells you that there is space in the buffer, and it is OK to push data to the UART. Of course at the startup the UART buffer is empty, and you are getting an interrupt as soon as you enable it. It is not a matter of timing. It is an expected behavior.
Such design makes the transmit flow very straightforward:
the mainline code prepares the buffer, and enables the interrupt
the ISR moves data to UART until either UART is full or there is no more data to send, and
once there is no more data to send, the ISR disables the interrupt

stm32 WFI not triggering

I am using an STM32L151 (Cortex-M3) and configuring an external interrupt on a gpio pin:
/* Enable clocks */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_SYSCFG, ENABLE);
RCC_APB1PeriphClockCmd(RCC_APB1Periph_SPI3, ENABLE);
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOA, ENABLE);
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOB, ENABLE);
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOC, ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM9, ENABLE);
/* ExtInt Input */
GPIO_InitTypeDef GPIO_InitStr;
GPIO_InitStr.GPIO_Speed = GPIO_Speed_40MHz;
GPIO_InitStr.GPIO_Mode = GPIO_Mode_IN;
GPIO_InitStr.GPIO_PuPd = GPIO_PuPd_DOWN;
GPIO_InitStr.GPIO_Pin = GPIO_Pin_13;
GPIO_Init(GPIOC, &GPIO_InitStr);
/* Interrupts on EXTINT */
SYSCFG_EXTILineConfig(EXTI_PortSourceGPIOC, EXTI_PinSource13);
EXTI_InitTypeDef ExtiInitStr = {EXTI_Line13, EXTI_Mode_Interrupt, EXTI_Trigger_Rising, ENABLE};
EXTI_Init(&ExtiInitStr);
NVIC_InitTypeDef NvicInitStr = {EXTI15_10_IRQn, 0, 0, ENABLE};
NVIC_Init(&NvicInitStr);
My main.c eventually reaches a point where I have:
__enable_irq();
//...program related code..
__ASM volatile ("wfi");
At this point, the processor does NOT wake up from a the external pin going high.
If I replace the WFI line instead with
while(1);
the interrupt is triggered properly. I tried to follow examples but did not find something different. (I use ST-Link/V2 debugger, GNU Tools for ARM Embedded Processors Toolchain & Eclipse plug-ins, with gdb and openOCD, if this matters)
Grateful for any hints!
My problem was actually solved by decreasing the PLL speed. My config is:
/* HCLK = SYSCLK /1*/
RCC->CFGR |= (uint32_t)RCC_CFGR_HPRE_DIV1;
/* PCLK2 = HCLK /1*/
RCC->CFGR |= (uint32_t)RCC_CFGR_PPRE2_DIV1;
/* PCLK1 = HCLK /1*/
RCC->CFGR |= (uint32_t)RCC_CFGR_PPRE1_DIV1;
/* PLL configuration */
RCC->CFGR &= (uint32_t)((uint32_t)~(RCC_CFGR_PLLSRC | RCC_CFGR_PLLMUL |
RCC_CFGR_PLLDIV));
RCC->CFGR |= (uint32_t)(RCC_CFGR_PLLSRC_HSI | RCC_CFGR_PLLMUL6 | RCC_CFGR_PLLDIV3);
And I verify that the problem is fixed when I replace RCC_CFGR_PLLMUL6 with RCC_CFGR_PLLMUL3. I cannot explain this, I don't know if it is related with the debugger speed or anything else.

STM32F4 interrupt handler for capture its not called

The code below uses the capture compare feature of TIM1 channel 3 to capture rising edge on PE10, but its not working, the interrupt handler its not called. I am not that good at this embedded stuff, so can somebody tell me if I am settings this correctly ?
#include "STM32/stm32f4xx_tim.h"
void TIM1_Config(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
/* TIM1 clock enable */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1, ENABLE);
/* GPIOA clock enable */
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOE, ENABLE);
/* TIM1 channel 3 pin (PE.10) configuration */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_Init(GPIOE, &GPIO_InitStructure);
/* Connect TIM pins to AF2 */
GPIO_PinAFConfig(GPIOE, GPIO_PinSource10, GPIO_AF_TIM1);
/* Enable the TIM1 global Interrupt */
NVIC_InitStructure.NVIC_IRQChannel = TIM1_CC_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
TIM_ICInitTypeDef TIM_ICInitStructure;
TIM_ICInitStructure.TIM_Channel = TIM_Channel_3;
TIM_ICInitStructure.TIM_ICPolarity = TIM_ICPolarity_Rising;
TIM_ICInitStructure.TIM_ICSelection = TIM_ICSelection_DirectTI;
TIM_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1;
TIM_ICInitStructure.TIM_ICFilter = 0x0;
TIM_ICInit(TIM1, &TIM_ICInitStructure);
/* TIM enable counter */
TIM_Cmd(TIM1, ENABLE);
/* Enable the CC3 Interrupt Request */
TIM_ITConfig(TIM1, TIM_IT_CC3, ENABLE);
}
void TIM1_CC_IRQHandler(void)
{
// .................
}
int StartCapture()
{
TIM1_Config();
while(1); /* Infinite loop */
}
If your TIM1_CC_IRQHandler() is getting called ONCE, then Dracog71's answer is correct. However, if your IRQHandler() is never firing, then there's something wrong in the initialization.
Here's a list of things you have to get right or the IRQ won't fire.
1) Make sure that the GPIO[A:E] clock is enabled for the pin you are using.
2) Likewise, make sure the clock is enabled for the TIMx you are using. Check where your TIMx lives. If you call RCC_APB2PeriphClockCmd() for a timer that lives on APB1, the compiler won't throw an error, but your timer will never work.
3) Double-check your pin's AF matches the datasheet's Alternative Function Mapping table (eg. AF1 == TIM1_CH3).
4) In your TIM_ICInitStructure, make sure TIM_Channel matches the channel you have chosen (in your case TIM_Channel_3).
5) Configure and enable the correct IRQ channel in the NVIC, eg. NVIC_InitStructure.NVIC_IRQChannel = TIM1_CC_IRQn;
6) Enable the interrupt: TIM_ITConfig(TIM1, TIM_IT_CC3, ENABLE);
7) Enable your timer: TIM_Cmd(TIM1, ENABLE);
Well, I guess my answer isn't required after 6 years. But maybe somebody else facing same problem will find it.
There may be a name conflict if you write in c++. If original prototype of interupt function is defined like C-function, and your implementation is C++function so it's just two different functions with the same name, and interupt will try to call an empty C-function or even may stack in endless loop. So that is why your c++ function may be newer called.
To solve this, just define your function like extern "C".
Maybe the interrupt enters the functions but does not know what to do, or enter ant he flag is still active and just enters once, you're missing the clear interrupt flag, try this:
/**
* #brief Capture Compare Handler
* #param None
* #retval None
*/
void TIM1_CC_IRQHandler()
{
if (TIM_GetITStatus(TIM1, TIM_IT_CC3) != RESET) <-- Add this
{
TIM_ClearITPendingBit(TIM1, TIM_IT_CC3); <-- This is important!
//TODO
}
}

How to initialize I2C on STM32F0?

Recently I've been trying to get the I2C bus working on the STM32F030F4P6 MCU, but with little luck.
I'm using an STM32F0 module and have found plenty of resources for the STM32F1 module I2C initialization, but nothing specific about the STM32F0 initialization/transfer process.
Here's my initialization code:
void i2c_init(uint8_t ownAddress)
{
GPIO_InitTypeDef GPIO_InitStructure;
I2C_InitTypeDef I2C_InitStructure;
// Enable GPIOA clocks
RCC_APB2PeriphClockCmd(RCC_AHBPeriph_GPIOA, ENABLE);
// Configure I2C1 clock and GPIO
GPIO_StructInit(&GPIO_InitStructure);
/* I2C1 clock enable */
RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C1, ENABLE);
/* I2C1 SDA and SCL configuration */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9 | GPIO_Pin_10;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_InitStructure.GPIO_OType = GPIO_OType_OD;
GPIO_Init(GPIOA, &GPIO_InitStructure);
/* I2C1 Reset */
RCC_APB1PeriphResetCmd(RCC_APB1Periph_I2C1, ENABLE);
RCC_APB1PeriphResetCmd(RCC_APB1Periph_I2C1, DISABLE);
/* Configure I2C1 */
I2C_InitStructure.I2C_AnalogFilter = I2C_AnalogFilter_Enable;
I2C_StructInit(&I2C_InitStructure);
I2C_InitStructure.I2C_Mode = I2C_Mode_I2C;
//I2C_InitStructure.I2C_DutyCycle = I2C_DutyCycle_2;
I2C_InitStructure.I2C_OwnAddress1 = ownAddress;
I2C_InitStructure.I2C_Ack = I2C_Ack_Enable;
I2C_InitStructure.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;
//I2C_InitStructure.I2C_ClockSpeed = ClockSpeed;
I2C_Init(I2C1, &I2C_InitStructure);
I2C_Cmd(I2C1, ENABLE);
}
In order to test to see if my setup was correct I designed some I2C transmission code that would transfer data in a never ending loop. Here's the code for that:
while(1)
{
I2C_SlaveAddressConfig(I2C1, RegName);
I2C_GenerateSTART(I2C1, ENABLE);
I2C_NumberOfBytesConfig(I2C1, 8);
I2C_SendData(I2C1,0b00000000);
I2C_GenerateSTOP(I2C1, ENABLE);
}
Where:
RegName = 0x75
SDA = GPIO_PIN_10 on GPIOA
SCL = GPIO_PIN_9 on GPIOA
I2C = I2C1
ownAdrress = 0x68
When I scope the I2C lines after I start this code I get a floating voltage around 160mV. When I step through the code every one of the I2C function calls happen and complete, so that's why I was thinking that it had something more so to do with my initialization of the pins themselves.
My problem is very similar to this thread, but was never answered:
https://my.st.com/public/STe2ecommunities/mcu/Lists/cortex_mx_stm32/Flat.aspx?RootFolder=https%3a%2f%2fmy%2est%2ecom%2fpublic%2fSTe2ecommunities%2fmcu%2fLists%2fcortex_mx_stm32%2fSTM32F0%20I2C%20code%20doesn%27t%20work&FolderCTID=0x01200200770978C69A1141439FE559EB459D7580009C4E14902C3CDE46A77F0FFD06506F5B&currentviews=1342
Edit 1: Here's my latest code; still not working (Edit 2: Updated to what I currently have; moved things into more correct locations):
void i2c_init(uint8_t ownAddress)
{
/* TypeDefs for GPIOA and I2C1 */
GPIO_InitTypeDef GPIO_InitStructure;
I2C_InitTypeDef I2C_InitStructure;
/* Enable GPIOA clocks and I2C1 clock enable */
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOA, ENABLE);
RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C1, ENABLE);
/* Configure I2C1 clock and GPIO */
GPIO_StructInit(&GPIO_InitStructure);
/* I2C1 SDA and SCL configuration */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9 | GPIO_Pin_10;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL; //UP
GPIO_InitStructure.GPIO_OType = GPIO_OType_OD;
/* GPIO AF Configuration -> GPIO_AF_1: USART2, CEC, Tim3, USART1, USART2,EVENTOUT, I2C1, I2C2, TIM15 */
GPIO_PinAFConfig(GPIOA, GPIO_PinSource9, GPIO_AF_1);
GPIO_PinAFConfig(GPIOA, GPIO_PinSource10, GPIO_AF_1);
GPIO_Init(GPIOA, &GPIO_InitStructure);
/* I2C1 Reset */
RCC_APB1PeriphResetCmd(RCC_APB1Periph_I2C1, ENABLE);
RCC_APB1PeriphResetCmd(RCC_APB1Periph_I2C1, DISABLE);
//I2C_DeInit(I2C1);
/* Configure I2C1 */
I2C_StructInit(&I2C_InitStructure);
I2C_InitStructure.I2C_AnalogFilter = I2C_AnalogFilter_Enable;
I2C_InitStructure.I2C_Mode = I2C_Mode_I2C;
I2C_InitStructure.I2C_OwnAddress1 = ownAddress;
I2C_InitStructure.I2C_Ack = I2C_Ack_Enable;
I2C_InitStructure.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;
I2C_Init(I2C1, &I2C_InitStructure);
I2C_Cmd(I2C1, ENABLE);
//I2C_AcknowledgeConfig(I2C1, ENABLE);
}
As you can see I added the two lines GPIO_PinAFConfig(GPIOA, GPIO_PinSource9, GPIO_AF_1); and GPIO_PinAFConfig(GPIOA, GPIO_PinSource10, GPIO_AF_1); where I found that GPIO_AF_1 had the alternate function of I2C1 from the STM32F0 Standard Peripheral bibliotheek.
Any other ideas? I've been playing around with the clocks to see if that changed anything and have been adding snippets of other people's code just to see if that has any effect on the output of my device.
Edit 3: I have tried pulling both the SDA and SCL lines up to VCC with a 1kohm resistor as instructed by this guide: https://electronics.stackexchange.com/questions/57121/i2c-pullup-resistor-calculations
->(3.3V-0.4)/3mA ~= 1kohm
Edit 4: After going through my code line by line I tried outputting various flag bit registers. Specifically these registers: isr = I2C1->ISR;, cr1 = I2C1->CR1;, and cr2 = I2C1->CR2;
The flag I get after initiating the I2C transfer handling with I2C_TransferHandling(I2C1, 0x02, 1, I2C_AutoEnd_Mode, I2C_Generate_Start_Write); was 0x8001 which can be deciphered down to two errors:
#define I2C_ISR_BUSY ((uint32_t)0x00008000) /*!< Bus busy */
and
#define I2C_ISR_TXE ((uint32_t)0x00000001) /*!< Transmit data register empty */
I've found some work arounds at this link here (remove the space after https: to go to the link -> stack overflow won't let me post more than 1 link for some reason): https: //my.st.com/public/STe2ecommunities/mcu/Lists/cortex_mx_stm32/Flat.aspx?RootFolder=%2Fpublic%2FSTe2ecommunities%2Fmcu%2FLists%2Fcortex_mx_stm32%2FSTM32L151RB%20I2C%20Busy%20flag%20always%20set&FolderCTID=0x01200200770978C69A1141439FE559EB459D7580009C4E14902C3CDE46A77F0FFD06506F5B&currentviews=690 that I'm looking to implement and will report back as soon as I try them out.
I have I2C working as master and slave on the F0. The main issue I can see with your code is that in master mode you absolutely must set the I2C_Timing initialisation structure member. See RM0091 for sample values that correspond to the frequency you want to generate on SCL. In slave mode the clock is recovered from the master so the timing member doesn't appear to be used.
As the others have said, external pullups to Vcc on SCL and SDA are not optional and must be present once per bus not per peripheral as you incorrectly stated in a comment. You were right to use the calculator to choose suitable values because the internal pullups in the STM32 at about 30-50K are far too weak for use as I2C pullups.
The problem is that you don't configure proper AF (Alternate Function) source for I2C pins. After reset registers that configure AF are all 0, and I2C's function is 1, so your I2C peripheral is in fact disconnected from the GPIOs.
Technically it makes no difference when you configure that, but it's best to do that before GPIO configuration to minimize any unwanted transitions on the pins.
Edit: You MUST have the pullups on the I2C pins - without them you have "low" level there, and I2C peripheral detects that as bus error, which obviously prevents it from working properly. Either connect external resistors, or at least enable internal pullups instead of "no pullups/no pulldowns" configuration.
Moreover - it's just not possible for an "open drain" pin to work properly without pullup.
The Core of Cortex M0 is different then Core of Cortex M3, STM32f030f4 has AHB and APB1 (bridged) only. The C code of STM32f1xx never be run under STM32f0xx.
Use STM32F0xx_Snippets_Package for solve your key problems.
I just noticed this too:
RCC_APB1PeriphResetCmd(RCC_APB1Periph_I2C1, ENABLE);
RCC_APB1PeriphResetCmd(RCC_APB1Periph_I2C1, DISABLE);
So you have disabled the clock after you enabled it. I don't see where you have re-enabled it later.
I notice that you are mapping the pins to AF_1 and that is for the UART function.
GPIO_PinAFConfig(GPIOA, GPIO_PinSource9, GPIO_AF_1);
GPIO_PinAFConfig(GPIOA, GPIO_PinSource10, GPIO_AF_1);
You need to map them to AF_4 to use the I2C function.
GPIO_PinAFConfig(GPIOA, GPIO_PinSource9, GPIO_AF_4);
GPIO_PinAFConfig(GPIOA, GPIO_PinSource10, GPIO_AF_4);

STM32F4 SPI Configuration SPI_Init causes assert_failed loop

I'm trying to configure SPI to work with a ST7565 GLCD library which is given here. For now, I'm trying to use SPI1 to achieve this. When the init function -which is given below- is called in main(), it causes the program to loop in assert_failed function.
void init_SPI1(void){
GPIO_InitTypeDef GPIO_InitStruct;
SPI_InitTypeDef SPI_InitStruct;
// enable clock for used IO pins
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
/* configure pins used by SPI1
* PA5 = SCK
* PA6 = MISO
* PA7 = MOSI
*/
GPIO_InitStruct.GPIO_Pin = GPIO_Pin_7 | GPIO_Pin_6 | GPIO_Pin_5;
GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStruct.GPIO_OType = GPIO_OType_PP;
GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_Init(GPIOA, &GPIO_InitStruct);
// connect SPI1 pins to SPI alternate function
GPIO_PinAFConfig(GPIOA, GPIO_PinSource5, GPIO_AF_SPI1);
GPIO_PinAFConfig(GPIOA, GPIO_PinSource6, GPIO_AF_SPI1);
GPIO_PinAFConfig(GPIOA, GPIO_PinSource7, GPIO_AF_SPI1);
// enable clock for used IO pins
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOE, ENABLE);
/* Configure the chip select pin
in this case we will use PE7 */
GPIO_InitStruct.GPIO_Pin = GPIO_Pin_7;
GPIO_InitStruct.GPIO_Mode = GPIO_Mode_OUT;
GPIO_InitStruct.GPIO_OType = GPIO_OType_PP;
GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_UP;
GPIO_Init(GPIOE, &GPIO_InitStruct);
GPIOE->BSRRL |= GPIO_Pin_7; // set PE7 high
// enable peripheral clock
RCC_APB2PeriphClockCmd(RCC_APB2Periph_SPI1, ENABLE);
/* configure SPI1 in Mode 0
* CPOL = 0 --> clock is low when idle
* CPHA = 0 --> data is sampled at the first edge
*/
SPI_InitStruct.SPI_Direction = SPI_Direction_1Line_Tx; // set to full duplex mode, seperate MOSI and MISO lines
SPI_InitStruct.SPI_Mode = SPI_Mode_Master; // transmit in master mode, NSS pin has to be always high
SPI_InitStruct.SPI_DataSize = SPI_DataSize_8b; // one packet of data is 8 bits wide
SPI_InitStruct.SPI_CPOL = SPI_CPOL_Low; // clock is low when idle
SPI_InitStruct.SPI_CPHA = SPI_CPHA_1Edge; // data sampled at first edge
SPI_InitStruct.SPI_NSS = SPI_NSS_Soft; // set the NSS management to internal and pull internal NSS high
SPI_InitStruct.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_16; // SPI frequency is APB2 frequency / 4
SPI_InitStruct.SPI_FirstBit = SPI_FirstBit_MSB;// data is transmitted MSB first
SPI_Init(SPI1, &SPI_InitStruct);
SPI_Cmd(SPI1, ENABLE); // enable SPI1
}
I've noticed that program goes in infinite loop inside assert_failed function when it reaches SPI_Init() line:
SPI_Init(SPI1, &SPI_InitStruct);
The assert_failed function ( Default in Firmware Library) is below:
void assert_failed(uint8_t* file, uint32_t line)
{
/* User can add his own implementation to report the file name and line number,
ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
/* Infinite loop */
while (1)
{
}
}
I don't know what does it supposed to mean that it loops in assert_failed function. Is it a problem to do with the SPI configuration. I need guidance to understand the problem and generate a solution. Any help will be greately appreciated. Thanks in advance.
EDIT: I've checked inside of the SPI_Init function in stm32f4xx_spi.c
void SPI_Init(SPI_TypeDef* SPIx, SPI_InitTypeDef* SPI_InitStruct)
{
uint16_t tmpreg = 0;
/* check the parameters */
assert_param(IS_SPI_ALL_PERIPH(SPIx));
/* Check the SPI parameters */
assert_param(IS_SPI_DIRECTION_MODE(SPI_InitStruct->SPI_Direction));
assert_param(IS_SPI_MODE(SPI_InitStruct->SPI_Mode));
assert_param(IS_SPI_DATASIZE(SPI_InitStruct->SPI_DataSize));
assert_param(IS_SPI_CPOL(SPI_InitStruct->SPI_CPOL));
assert_param(IS_SPI_CPHA(SPI_InitStruct->SPI_CPHA));
assert_param(IS_SPI_NSS(SPI_InitStruct->SPI_NSS));
assert_param(IS_SPI_BAUDRATE_PRESCALER(SPI_InitStruct->SPI_BaudRatePrescaler));
assert_param(IS_SPI_FIRST_BIT(SPI_InitStruct->SPI_FirstBit));
assert_param(IS_SPI_CRC_POLYNOMIAL(SPI_InitStruct->SPI_CRCPolynomial));
Since the library is locked, I cant get to type anything inside to debug in Live Watch. (I'm using IAR EWARM)
It loops in assert() because the assert failed, so the loop is there to stop further execution.
Just step up on your stack so that you can see which assert in the peripheral library it was that failed. The library does pretty extensive validation of its parameters, so probably something is wrong in one of your calls.
UPDATE It seems you never initialize the CRCPolynomial field, but it's asserted upon. I suggest adding a call to SPI_StructInit() to make sure your init struct is sanely initialized, before you start setting it up according to your application's wishes.

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