Datasheet

Table Of Contents
Functional overview STM32WLE5J8/JB/JC
36/135 DS13105 Rev 4
3.13 General-purpose inputs/outputs (GPIOs)
Each of the GPIO pins can be configured by software as output (push-pull or open-drain), as
input (with or without pull-up or pull-down) or as peripheral alternate function. Most of the
GPIO pins are shared with digital or analog alternate functions. Fast I/O toggling can be
achieved thanks to their mapping on the AHB2 bus.
The I/Os alternate function configuration can be locked if needed following a specific
sequence in order to avoid spurious writing to the I/Os registers.
3.14 Directly memory access controller (DMA)
The DMA (direct memory access) is used to provide high-speed data transfer between
peripherals and memory, as well as memory to memory. Data can be quickly moved by
DMA without any CPU actions. This keeps CPU resources free for other operations.
The DMA controller has 14 channels in total. A full cross matrix allows the peripherals, with
DMA support, to be mapped on any of the available DMA channels. Each DMA channel has
an arbiter for handling the priority between DMA requests.
The DMA main features are listed below:
14 independently configurable channels (requests)
a full cross matrix between peripherals and all 14 channels and an hardware trigger
possibility through the DMAMUX1
software programmable priorities between requests from channels of one DMA (four
levels: very-high, high, medium, low), plus hardware priorities management in case of
equality (example: request 1 has priority over request 2)
independent source and destination transfer size (byte, half-word, word), emulating
packing and unpacking. Source/destination addresses must be aligned on the data
size.
support for circular buffer management
three event flags (DMA half-transfer, DMA transfer complete and DMA transfer error),
logically ORed together in a single interrupt request for each channel
memory-to-memory transfer
peripheral-to-memory, memory-to-peripheral, and peripheral-to-peripheral transfers
access to Flash memory, SRAM, APB and AHB peripherals, as source and destination
programmable number of data to be transferred (up to 65536)
DMAMUX1 is used to route the peripherals with DMA source support, to any DMA channel.
Table 11. DMA1 and DMA2 implementation
Feature DMA1 DMA2
Number of channels 7 7