Trouble with Multiple Interrupts in ARM Assembly: Unresponsive Peripheral
I need help solving I'm working on a personal project and I'm encountering an issue while working with ARM assembly on an STM32 microcontroller where I need to handle multiple interrupts for different peripherals. I configured the NVIC and set the interrupt priorities, but when one peripheral interrupt is triggered, it seems to block subsequent interrupts from being handled properly. I expect the second interrupt to be processed after the first one, but instead, I'm just seeing the first one being serviced repeatedly. Here’s a snippet of the initialization code for the interrupts: ```assembly ; Enable IRQ for TIM2 and EXTI0 LDR R0, =NVIC_ISER LDR R1, =0x00000003 ; Enable TIM2 and EXTI0 STR R1, [R0] ; Set priority for TIM2 LDR R0, =NVIC_IPR LDR R1, =0x00000002 ; Set priority level for TIM2 STR R1, [R0] ``` In my interrupt handlers, I am clearing the interrupt flags, but it seems like the second handler is never getting called. My current setup uses the STM32F4xx standard peripheral library. I've checked the interrupt vector table and the handlers are correctly defined, but I still see strange behavior, especially when both peripherals trigger at nearly the same time. Also, I verified my system clock configurations, ensuring that the interrupts are set to a high priority. I am using the following code in the TIM2 interrupt handler: ```assembly TIM2_IRQHandler: ; Check and clear TIM2 interrupt flag LDR R0, =TIM2_SR LDR R1, [R0] BIC R1, R1, #0x01 ; Clear update flag STR R1, [R0] ; Additional handling code BX LR ``` I would appreciate any insights into why the second interrupt isn’t getting serviced. Is there a specific setting I might be missing in the NVIC configuration, or could it be related to the way I’m managing the interrupt flags? Additionally, what are best practices for ensuring that high-frequency interrupts can coexist without blocking each other in ARM assembly? This is part of a larger application I'm building. My team is using Assembly for this CLI tool. Any advice would be much appreciated. I'm on Linux using the latest version of Assembly. What's the best practice here?