
RM0453 Rev 2
479/1454
RM0453
DMA request multiplexer (DMAMUX)
497
14
DMA request multiplexer (DMAMUX)
14.1 Introduction
A peripheral indicates a request for DMA transfer by setting its DMA request signal. The
DMA request is pending until it is served by the DMA controller that generates a DMA
acknowledge signal, and the corresponding DMA request signal is deasserted.
In this document, the set of control signals required for the DMA request/acknowledge
protocol is not explicitly shown or described, and it is referred to as DMA request line.
The DMAMUX request multiplexer enables routing a DMA request line between the
peripherals and the DMA controllers of the product. The routing function is ensured by a
programmable multi-channel DMA request line multiplexer. Each channel selects a unique
DMA request line, unconditionally or synchronously with events from its DMAMUX
synchronization inputs. The DMAMUX may also be used as a DMA request generator from
programmable events on its input trigger signals.
The number of DMAMUX instances and their main characteristics are specified in
The assignment of DMAMUX request multiplexer inputs to the DMA request lines from
peripherals and to the DMAMUX request generator outputs, the assignment of DMAMUX
request multiplexer outputs to DMA controller channels, and the assignment of DMAMUX
synchronizations and trigger inputs to internal and external signals depend on the product
implementation, and are detailed in
.