Nations Technologies Inc.
Tel
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+86-755-86309900
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info@nationstech.com
Address: Nations Tower, #109 Baoshen Road, Hi-tech Park North.
Nanshan District, Shenzhen, 518057, P.R.China
133
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631
DMA controller
Introduction
The DMA controller can access totally 5 AHB slaves: Flash, SRAM, ADC, ABP1 and APB2. DMA Controller is
controlled by CPU to perform fast data movement from source to destination. After configuration, data can be
transferred without CPU intervention. Thus, CPU can be released for other computation/control tasks or save overall
system power consumption.
MCU’s main backbone is a multi-layer AHB-Lite bus structure with round-robin arbitration scheme. DMA and CPU
core can access different slaves in parallel or same slaves sequentially.
DMA controller has 8 logic channels. Each logic channel is to serve memory access requests from single or multiple
peripherals. Internal arbiter controls the priority of different DMA channels.
Main features
DMA main features:
8 DMA channels which can be configured independently.
Each DMA channel supports hardware requests and software triggers to initiate transfer, and is configured by
software.
Each DMA channel has dedicated software priority level (DMA_CHCFGx.PRIOLVL [1:0] bits, corresponding
to 4 levels of priority) which can be configured individually. Channels with the same software priority level will
further compare hardware index (channel number) to decide final priority (lower index number channel will has
higher priority).
Configurable source and destination size. Address setting should correspond to data size.
Configurable circular transfer mode for each channel.
Each channel has 3 independent event flags and interrupts (Transfer complete, Half transfer, Transfer error), and
1 global interrupt flag (set by logical OR of 3 events).
Support three transfer types which are Memory-to-Memory, Memory-to-Peripheral and Peripheral-to-Memory.
Access totally 5 AHB slaves: Flash, SRAM, ADC, APB1 and APB2.
Configurable data transmit number (0~65535).