Datasheet

Table Of Contents
DS13105 Rev 4 37/135
STM32WLE5J8/JB/JC Functional overview
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3.15 Interrupts and events
3.15.1 Nested vectored interrupt controller (NVIC)
The devices embed an NIVC able to manage 16 priority levels, and to handle up to
62 maskable interrupt channels plus the 16 interrupt lines of the Cortex-M4.
The NVIC benefits are the following:
low-latency interrupt processing
interrupt entry vector table address passed directly to the core
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
The NVIC hardware block provides flexible interrupt management features with minimal
interrupt latency.
3.15.2 Extended interrupt/event controller (EXTI)
The EXTI manages wakeup through configurable and direct event inputs. It provides wake-
up requests to the power control, and generates interrupt requests to the CPU NVIC and
events to the CPU event input.
Configurable events/interrupts come from peripherals that are able to generate a pulse and
allow the selection between the event/interrupt trigger edge and a software trigger.
Direct events/interrupts come from peripherals having their own clearing mechanism.
3.16 Analog-to-digital converter (ADC)
A native 12-bit ADC is embedded into the devices. It can be extended to 16-bit resolution
through hardware oversampling. The ADC has up to 12 external channels and four internal
channels (temperature sensor, voltage reference, VBAT monitoring, DAC output). The ADC
performs conversions in single-shot or scan mode. In scan mode, automatic conversion is
performed on a selected group of analog inputs.
The ADC frequency is independent from the CPU frequency, allowing maximum sampling
rate of ~2 Msps even with a low CPU speed. An auto-shutdown function guarantees that the
ADC is powered off except during the active conversion phase.
The ADC can be served by the DMA controller. It can operate in the whole V
DD
supply
range.
The ADC features a hardware oversampler up to 256 samples, improving the resolution to
16 bits. Refer to the application note Improving STM32 Series ADC resolution by
oversampling (AN2668).
An analog watchdog feature allows very precise monitoring of the converted voltage of one,
some or all scanned channels. An interrupt is generated when the converted voltage is
outside the programmed thresholds.