• 2020-05-01 status

    Konrad Beckmann05/01/2020 at 09:26 0 comments

    This project has not gotten a lot of my attention since I made the first rev and initial bringup.

    However, people seem to find their way here and I thought I'd just leave a note about the current status of the project.

    This board was designed in a rush, in order to get it done for 35C3, 2018-12-27. The goal was to have a cheap ECP5 board with a high speed PC interface and a bunch of IOs.

    What is working?

    • ECP5 FPGA works
      • It can be configured through JTAG.
      • Clock input from FT600 and oscillator works.
      • SDRAM works.
      • Have tested a LiteX build using SDRAM and micropython.
    • FT600 interface works
      • Can make transfers to and from the FPGA at maximum speed that the FT600 can handle, i.e. 200 MB/s.
      • USB-C connector and routing works, however it's a pain to solder since the pads are small and it has a row of hidden pads behind the outer row. Found a different connector with pins for the hidden row instead, UJ31-CH-31-SMT-TR.  Have tried it and it is much easier to rework.

    What needs to be fixed?

    • FT_CLK is not routed to a clock input
    • The JTAG connector has a weird pinout.
    • Pin 33 on the wide connector is NC on the 12F variant
    • Flash needs pull-resistors.
    • Improve routing for high speed IOs. Even if no high speed connector is used, the signals should be routed and exposed together (A and B pins from the FPGA).

    Software?

    • Started working on a migen project that was supposed to expose an easy way to communicate with the FPGA at high speeds.
    • Initial code sort of works but relies on the proprietary drivers which is a pain.
    • Still requires the fpga to be programmed through JTAG. Need a bootloader that loads the bitstream to flash and boots into it.
    • Got bored and haven't made any significant progress in a while.

    RevB

    I started working on a RevB but haven't really done any progress since I got stuck trying to figure out which high speed connectors to use. HDMI, SATA, USB-C, SYZYGY ...

    At this point this project is pretty much on hold indefinitely. I started a dedicated HDMI capture/transmit project here, however after I learned about the Camlink and the reverse engineering progress that has already been made with that, there is no point in continuing that project.

    However!

    I made another board for 36C3, 2019-12-27, called pergola. That project is very much alive, please check it out instead. hackaday.io project page.