Re: [lwip-users] stm32 ethernet interrup priority

Hi,

Yes you have a problem...

Cortex-M3 has a priority level mechanism a bit different from other micro's.

In FreeRTOS its a bit not clear...

Your FreeRTOS time tick is interrupt driven and has a priority.

Also all your devices interrupts have priorities.

In FreeRTOS you have function calls that are used in your application code and similar function

that can be called from interrupt (prefix FromISR...)

In order to have a stable code running with FreeRTOS you must set all interrupts that may need to

be stopped by the OS to have a lower interrupt priority.

Cortex interrupt priority

15 lowest

0 highest

If you set your OS time tick interrupt priority to 5 your UART, TCP etc must be set to 5 + something.

If you do not set it like that you will get strange behavior.

I suggest downloading an ST example and see how they set it properly.

Good luck,

Noam.

From: lwip-users <lwip-users-bounces+address@hidden> on behalf of Erkan Ersoy <address@hidden>
Sent: Saturday, August 20, 2016 12:54 PM
To: Mailing List for LwIP Users
Subject: [lwip-users] stm32 ethernet interrup priority

Hello;

I am trying to implement usart interrupt to my project

So iread freertos stm32 interrupt warnings and set i lilk that

/* Enable the Ethernet global Interrupt */

NVIC_InitStructure.NVIC_IRQChannel = ETH_IRQn;

NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority =2;

NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;

NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;

NVIC_Init(&NVIC_InitStructure);

//USART 5 interrupt

NVIC_InitTypeDef NVIC_InitStruct;

NVIC_InitStruct.NVIC_IRQChannel = UART5_IRQn;

NVIC_InitStruct.NVIC_IRQChannelCmd = ENABLE;

NVIC_InitStruct.NVIC_IRQChannelPreemptionPriority = configMAX_SYSCALL_INTERRUPT_PRIORITY;

NVIC_InitStruct.NVIC_IRQChannelSubPriority = 1;

NVIC_Init(&NVIC_InitStruct);

But I begin to have system freezes so i changed it like that