OpenSource FPGA dev. kit with DSO/logic analyzer module - Page 1
Forum section: electronics / projects

author: josko
author_rank: Newbie
timestamp: June 26, 2013, 10:29:26 pm
content: Hello,I would like to introduce myself first. I am student of Computer engineering at Brno University of Technology.I am interested in two extremely different parts of electrical engineering and that is vintage vacuum tube electronics and computers.Since I only own old vacuum tube oscilloscope I have decided to make myself better one.And this little project was my bachelor's thesis and I would like to share it as open hardware and software with you guys.It is basic FPGA dev kit with FTDI USB 2.0 interface and 8MBIT SDRAM (intended as sample memory) and DSO module.Basic specs:FPGA dev board- four layer board, with Spartan 6 LX25, FT2232H, configuration flash, 8MBIT SDRAM and IO headers.DSO module- two layer board, 125MHz samplig rate (would be usable to 200MHz or more with better oscillator) and 100MHz analog BW, 16bit logic analyzer.Everyone is welcome to improve my design, firmware or software here on github:https://github.com/josko7452/qwave-projectI will try to answer any questions about my HW/FW/SW design if anyone would be interested..FPGA board is fully working and could be used for various purposes apart of using DSO module. DSO module has some quirks (noise), but it is usable as well. I am attaching photo of manufactuered boards and screenshot of measuring 3MHz triangle wave from really crappy signal generator that was available in my university lab...PS: I know that Dave doesn't like USB DSOs but I silently hope for thumbs upEven thought it couldn't replace real scope, I find it still handy because it is really portable being 10x4x2cm and I always carry my laptop anyway...

author: digsys
author_rank: Unknown
timestamp: June 27, 2013, 11:34:58 am
content: Congratulations !! It's great to see future techies attempt what are actually quite advanced projects, and to actually have them working.I monitor / mentor / mark several post-grad / phd groups, and am DAMN impressed with some of the student achievements these days.Did you write all the Firmware and PC software as well yourself? Did you work in a team? I hope others take you up on your offer.Once again, CONGRATS.

author: josko
author_rank: Newbie
timestamp: June 27, 2013, 02:12:18 pm
content: digsys:Thank you! It was one man show, so it was all created by me. Only both PCB are professionaly manufactured and also FPGA board was professionaly assemled due to BGA package of used FPGA, DSO module was soldered by hand with iron beause it is has parts on both sides and I really didn't want to glue them to solder them in reflow oven...Sure firmware and especially software needs some tweaks and more features to be really complete measurement solution, now I am thinking about making intensity graded display just because it's so cool, but I would also like to make trigger selection more complex now it is just rising/falling edge for analog signals and pattern matching for logic analyzer, pretty much just basic..There are some noise issues on analog inputs (when setting very high input sensitivity) but, the thing with this is that I have no access to school lab in summer, so I am basically constrained by my home equipment and it's only soldering iron, multimeter, lab supply and 2MHz vacuum tube scope. So any new revisions of HW must wait for masters semesters. Also manufacturing of these boards is quite expensive, so I had just one prototype allowed to manufacture by my school (they funded it).Also there was problem with Farnell and their parts availability, the promised to deliver 200MHz oscillator at the end of April but it was not available on 5th of May so I had to order 125MHz oscillator at the end, so it could really be more useful with 200MHz samplig rate...