Direct Memory Access Controller (Dma); Interrupts And Events; Nested Vectored Interrupt Controller (Nvic); Extended Interrupt/Event Controller (Exti) - STMicroelectronics STM32F038C6 Manual

STM32F038x6
3.8

Direct memory access controller (DMA)

The 5-channel general-purpose DMAs manage memory-to-memory, peripheral-to-memory
and memory-to-peripheral transfers.
The DMA supports circular buffer management, removing the need for user code
intervention when the controller reaches the end of the buffer.
Each channel is connected to dedicated hardware DMA requests, with support for software
trigger on each channel. Configuration is made by software and transfer sizes between
source and destination are independent.
DMA can be used with the main peripherals: SPIx, I2Sx, I2Cx, USARTx, all TIMx timers
(except TIM14) and ADC.
3.9

Interrupts and events

3.9.1

Nested vectored interrupt controller (NVIC)

The STM32F0xx family embeds a nested vectored interrupt controller able to handle up to
32 maskable interrupt channels (not including the 16 interrupt lines of Cortex
priority levels.
•
Closely coupled NVIC gives low latency interrupt processing
•
Interrupt entry vector table address passed directly to the core
•
Closely coupled NVIC core interface
•
Allows early processing of interrupts
•
Processing of late arriving higher priority interrupts
•
Support for tail-chaining
•
Processor state automatically saved
•
Interrupt entry restored on interrupt exit with no instruction overhead
This hardware block provides flexible interrupt management features with minimal interrupt
latency.
3.9.2

Extended interrupt/event controller (EXTI)

The extended interrupt/event controller consists of 24 edge detector lines used to generate
interrupt/event requests and wake-up the system. Each line can be independently
configured to select the trigger event (rising edge, falling edge, both) and can be masked
independently. A pending register maintains the status of the interrupt requests. The EXTI
can detect an external line with a pulse width shorter than the internal clock period. Up to 38
GPIOs can be connected to the 16 external interrupt lines.
3.10

Analog-to-digital converter (ADC)

The 12-bit analog-to-digital converter has up to 10 external and 3 internal (temperature
sensor, voltage reference, VBAT voltage measurement) channels and performs conversions
in single-shot or scan modes. In scan mode, automatic conversion is performed on a
selected group of analog inputs.
The ADC can be served by the DMA controller.
DocID026079 Rev 3
Functional overview
® -M0) and 4
15/102
22