Nios® II Embedded Design Suite (EDS)
Support for Embedded Development Tools, Processors (SoCs and Nios® II processor), Embedded Development Suites (EDSs), Boot and Configuration, Operating Systems, C and C++
Intel Support hours are Monday-Fridays, 8am-5pm PST, except Holidays. Thanks to our community members who provide support during our down time or before we get to your questions. We appreciate you!

Need Forum Guidance? Click here
Search our FPGA Knowledge Articles here.
12409 Discussions

Sustained USB 2.0 transfer rates with a Nios II-based system running Linux

Honored Contributor II



I'm currently developing a 100 MHz Nios II (w/ MMU)-based system that will be booting Linux and will utilize, among other system components, a USB 2.0 Host Controller and a DMA controller to transferring data to/from a USB 2.0 device. 


I have performed some initial USB 2.0 performance testing with our current system but I'm currently only able to achieve approximately a 3 MByte per second sustained read and write transfer rate with a USB 2.0 flash drive. I have measured the sustained read transfer rate of a USB 2.0 flash drive in excess of 30 MBytes per second when connected to a PC. While I don't expect to be able to reach a 30 MByte read transfer rate on our Nios II Linux-based system, I was hoping we could reach a 10 - 15 MByte per sustained transfer read rate. 


Does anyone have experience of hosting USB 2.0 devices that runs Linux on a Nios II processor that also utilizes a USB 2.0 host controller core that is also integrated with a DMA engine? If so, what sustained read and write transfer rates were you able to achieve? Where was the bottleneck in the data transfer path? Nios II to/from the USB Host Controller? Nios II to/from the external SDRAM memory? 


Any feedback would be appreciated. 


- Brad
0 Kudos
2 Replies
Honored Contributor II

Nios ii fast?

Honored Contributor II

Hi flz47655, 


Yes, we are using the Nios II fast processor core.