usb to fpga - Page 1
Forum section: electronics / general

author: legacy
author_rank: Super Contributor
timestamp: April 10, 2018, 11:21:04 am
content: I need to develop a fast-usb-link (10Mbyte/sec at least, 20Mbyte/sec would be better) from a linux-host to a fpga-target (3.3V)what do you suggest?

author: legacy
author_rank: Super Contributor
timestamp: April 10, 2018, 11:55:47 am
content: FT232H? umm, what about the host-side, I mean I need to write a kernel-module for a MIPS-LE machine

author: SiliconWizard
author_rank: Super Contributor
timestamp: April 10, 2018, 12:02:51 pm
content: You don't need to develop any module, use libusb. It's available on pretty much any Linux distribution. FTDI's own drivers for Linux are based on libusb. I don't think they have drivers for MIPS targets, but you can use libftdi which is open source and also uses libusb.

author: legacy
author_rank: Super Contributor
timestamp: April 10, 2018, 01:30:33 pm
content: Code:dev-libs/libusbHomepage: http://libusb.info/ https://github.com/libusb/libusbDescription: Userspace access to USB devices

author: rhb
author_rank: Super Contributor
timestamp: April 10, 2018, 11:38:16 pm
content: Quote from: legacy on April 10, 2018, 11:55:47 amA MIPS-LE machine? Are you running a DECstation?

author: lucazader
author_rank: Regular Contributor
timestamp: April 11, 2018, 01:18:12 am
content: Not sure what the linux driver situation is, but these cypress chips are aftern used as the USB frontend to an FPGA device.http://www.cypress.com/products/ez-usb-fx2lp

author: xaxaxa
author_rank: Regular Contributor
timestamp: April 11, 2018, 06:05:21 am
content: I've always used a usb3343 plus the open source usb-serial vhdl core athttp://jorisvr.nl/article/usb-serial,which can easily do 30MB/s transfer. It shows up as a usb CDC (communications device class) device which most OS's have built in drivers for (it works out of the box on linux and mac os, but needs a special .inf file on windows). This is probably the cheapest solution.I wouldn't use anything from ftdi in my products because of the attitude they have shown towards customers (look up "ftdi gate"), but there is also a usb3 to fifo ftdi chip that can do much higher transfer rates (only limited by usb3).

author: legacy
author_rank: Super Contributor
timestamp: April 11, 2018, 07:27:38 am
content: Quote from: rhb on April 10, 2018, 11:38:16 pmmodern RISCs made in China are MIPS64-LE

author: legacy
author_rank: Super Contributor
timestamp: April 11, 2018, 07:33:38 am
content: thanks guys

author: legacy
author_rank: Super Contributor
timestamp: April 11, 2018, 01:38:44 pm
content: any low-cost (<200Euro) fpga (Xilinx is my choice) with usb3343 onboard?

author: rhb
author_rank: Super Contributor
timestamp: April 11, 2018, 02:16:09 pm
content: Quote from: legacy on April 11, 2018, 07:27:38 amThe R2000 was pin selectable for byte sex. DEC chose LE and SGI chose BE.

author: legacy
author_rank: Super Contributor
timestamp: April 11, 2018, 03:19:15 pm
content: Quote from: rhb on April 11, 2018, 02:16:09 pmUmm, the SONY Playstation1's CPU is a good example of MIPS design where you can set the endianness. SONY went for LE, the firmware is LE, and every game ever developed is LE.I am more interested in MIPS32r2 and MIPS64r2. Although nowadays MIPS are usually used for router products, a few companies located in China have already designed ATX motherboards for daily computing needs, and usually, you can't set its endianness by setting a bit during the early bootstrapping. It's hardcoded, thus you have to consider their products as LE machines.Concerning linux, there is kernel support for LE<--> BE. Even if some kernel-driver are still bugged due to the endianness

author: legacy
author_rank: Super Contributor
timestamp: April 11, 2018, 03:21:20 pm
content: anyway, my application is byte-oriented, thus not prone to endianness-issue