Design Of Low Power Direct Memory Access Module In Microcontroller Unit

Direct memory access is an important module of all modern Microcontroller Unit.DMA supports the interaction between hardware devices with different transmission speeds,and this interaction does not have to rely on the interrupt load of the CPU(Central Processing Unit).Otherwise,the CPU will need to copy the data and data of each running program from the source to the buffer,and then write them back to a new destination address.During this time,the CPU will not be able to perform other tasks The use of DMA for data transmission can reduce the workload of the CPU and improve the system efficiency of the microprocessor.This paper designs a DMA with strong data handling function.Each channel can support up to 216 data transfers at a time;support the unequal transmission of data bit width,source address data and destination address data can be configured to 8bits,16 bits 32bits;channel priority includes inherent priority and software configuration priority,the inherent priority gradually increases from channel 1 to channel 7,software configurable priority up to four types:low,medium,high,very high;data handling direction includes Three types: mem2 mem,mem2peri,peri2 mem.And after the design of DMA is completed,the power consumption of DMA is improved,and the clock gating technology is introduced,which greatly reduces the power consumption of DMA in the data transmission process.Using the MCU development platform Keil C51 software to write a test program,the design function verification of the module was carried out.And completed the simulation verification on VCS,confirmed that the DMA module in various modes of data handling is correct.Using Synopsys' Prime Time software for power consumption analysis,the DMA module was compared with or without the introduction of clock gating to compare the power consumption when carrying the same batch of data.The results show that the DMA dynamic power consumption of the clock gating technology has dropped by 31.9%.It is of great significance to improve the system efficiency of MCU and reduce the power consumption of MCU.