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What happens when multiple interrupts occur?
Answer: When multiple interrupt requests of an identical level occur simultaneously, priority is given to the interrupt source that has the smaller vector number. For details, please see the Interrupt Source Priority Register n (IPRn) section in the Interrupt Controller chapter.
How multiple interrupts that occur simultaneously are handled?
Multiple interrupt requests require a mechanism to handle each interrupt. Two or more interrupts requests may also be received simultaneously. Moreover, a new interrupt may be received by the processor while an earlier interrupt is being handled.
When an interrupt is triggered what register is placed on the stack?
Order of register saving, when they are pushed to stack is defined by architecture. in real mode, on interrupt hardware pushes FLAGS, push CS, push IP; iret instruction will reload them to return to user.
How does STM32 support interrupt based UART communication?
In STM32 Architecture, using the HAL libraries shortens the development process significantly and the community helps the developers on the process. In the case of the interrupt based uart communication, the high level HAL_UART_Receive_IT function can be used with its callback HAL_UART_RxCpltCallback.
What happens when multiple UART interrupts are triggered?
This means for every byte received, two interrupts are triggered. Now both UARTs can receive and transmit, and it is very much possible that both UARTs do receive a byte at the same time – now both will get a RXNE interrupt and trigger a TXE interrupt on the other UART.
Can a UART Receive a byte at the same time?
Now both UARTs can receive and transmit, and it is very much possible that both UARTs do receive a byte at the same time – now both will get a RXNE interrupt and trigger a TXE interrupt on the other UART. But only one ISR can be processed at the same time – what happens with the other ones?
How to deal with the constant buffer size in UART?
In this post, we will explain an effective way of the interrupt based UART communication. It is easier to deal with the constant buffer size on the interrupt based communications. The interrupt can be triggered by initiating the communication with receiving a determined number of characters.