Any examples how to do it, in case it is possible?
@panther03 i'm using e2kgh's boards for artix7, but any artix7 would do everything worked on f32c artix7 including DDR3 RAM on axi bus as well as SDRAM. DDR3 has More latency than SDRAM but also more bandwidth. zynq may work but I didn't manage to get stable DDR3 RAM on vendor specific axi bus implementation (zybo board). RAM on the first glance works but has small corruption sector every cca 64KB :). SDRAM or zynq would normally work but usially not used with zynq boards
@janrinze_gitlab pulling down PROGRAMN pin using other pin connected to it (we named it in constraints something like user_programn) will reset FPGA by requesting reload of bitstream. Note that if board has multiboot flashed (newer boards do), programn requests load of the next multiboot image in chain. However our boards have battery and RTC so they can power down and wake up in few seconds that would really make it everything reload from start, but of course needs a lot of hardware to be preset for this to happen
@e2kgh I know only for PLL fine phase adjustment allowed during runtime but not freq change. There are vendor specific parameters that ecp5pll generates for different clock combination and if dynamically changed using some yosys hack, this parameters need to be made in table. A not so elegant solution could be many bitstreams (one for each clock/resolution) either in flash and multiboot switches them circular and sequentially or on SD card and then esp32 switches them on any order ecp5.prog()
Absolutely yes and I was also thinking to squeeze some PCB space (difficult :) to fit a placeholder of I2C/SPI programmable clock generator 0-200 MHz. Maybe there's some possibility with ESP32 to generate something, seems up to 40MHz is possible https://github.com/vdeschwb/esp32-signal-generator but something higher would be nice to have
People here might find https://github.com/Blokkendoos/AACircuit entertaining! -- Draw electronic circuits with ASCII characters.
Somewhat the reason why I never have time to play with my ULX3S :-)
Related; I bought two ulx3s (85f) and one of the two reboots itself at random intervals (between 5-15seconds) when running litex, is there any way to get a replacement for the defective one?
There are also few boards available in Envox store
Unfortunately prices are currently bit higher, as I am picking parts in small quantities and from everywhere.
@djhardrich:matrix.org Yes we can arrange replacements, but board could be completely good and reset if something in design is on the edge.
Better would be if you can track problem and somehow prove that we have HW problem - like if memory is bad it should fail long memtest run.
@djhardrich:matrix.org if possible make a simple .bit example that for example turns on green LED if board is "good" for your use and goran can then pick board that passes your test. Note that this board may not pass different test, when things get overclocked, some parts from FPGA silicon behave better than others, it's random behaviour, different between FPGA chips from same series and there's no general solution except to optimize code or use lower clock rate
Will try to put something together to show a “pass,” I was using this/the litex ulx3s example project, the board that doesn’t cooperate resets itself before it can receive the software to boot via litex_term: https://github.com/dlobato/cps1-musicbox
You can load this image with fujprog https://github.com/intergalaktik/ulx3s-bin/blob/master/fpga/f32c/f32c-85k-vector-v20/ulx3s_v20_85f_f32c_selftest_100mhz_flash.img
You will see on HDMI screen if everything is working.
For second test you can try to run this Linux - https://github.com/emard/ulx3s-bin/tree/master/fpga/litex/linux
And - this is wrong for you --> SDRAM: 65536KiB 32-bit @ 24MT/s (CL-2 CWL-2)
If you do not have blue board - you will need to setup SDRAM to 32Mb
All green boards we are selling lately have 32Mb of SDRAM
We only did 64Mb (blue boards) batch once - so there are around 100 boards with 64Mb chip
It is a green board (32mb SDRAM), will flash and test, also thank you for the notes, will report back later tonight!
Hello everyone, I currently have a co-design ESP32/FPGA application and I would like to measure the power consumption. Would anyone know if there is a way to measure the FPGA power consumption on the board? Or can I only measure power consumption measuring the current on the US1 port?
6 replies
@qcabanes HI board has no direct means to monitor the power consumption. Some "hack" could be done by monitoring magnetic field around L1,2,3 inductors using e.g. simple pickup coils to differential inputs. One could measure duty cycle (time) how long are the coils energized and deduce power consumption
Hi here.
I am working with a 3.0.8 ulx3s (85) with 1.19.1 MicroPython on the esp.
I have a strange problem.
As soon as I flash the fpga (using openFPGALoader, the bitstream is loaded and the fpga "runs" fine the test)
my ESP32 becomes unreachable, with ampy (usb) but also over ip, which both worked before using openFPGALoader .
Any clue ?
Thanks
I am working with a 3.0.8 ulx3s (85) with 1.19.1 MicroPython on the esp.
I have a strange problem.
As soon as I flash the fpga (using openFPGALoader, the bitstream is loaded and the fpga "runs" fine the test)
my ESP32 becomes unreachable, with ampy (usb) but also over ip, which both worked before using openFPGALoader .
Any clue ?
Thanks
FPGA internally should run usb-serial bridge (TX/RX bypass) in order to be accessible over USB and take care about not to drive WIFI_EN=0, as this would disable ESP32. WIFI_EN has onboard pullup to keep it 1 if undriven. However, if ESP32 still disables from WIFI/IP - it is also possible, in some cases, especially with some resolution of video HDMI generation FPGA (project for apple2 emulation has this issue) can make some RF noise that affect WIFI range and connection drops often. Plug off HDMI cable and check is it getting better
Hi @emard
Thanks for your answer.
This seems not be related to hdmi, I unplugged my cable, it did not change, but I was not using hdmi anyway.
Even flashing the passthrough has the same effect.
After having flashed the passthrough, the only thing that succeeds is "reset" and only with esptool, nothing seems to work with ampy.
All this seems related to the version of micropython; because when I flash back
esp32-idf3-20210202-v1.14.bin every works fine.
But my esp32-20220618-v1.19.1.bin has the issue.
I'd like to have something "more recent" than 1.14.
I am going to try some other versions.
Micropython 1.14 is good because it can umount SD card normally, later versions crash or reboot when SD is unmounted. I complained but they say it's not micropython that crashes but some build environment. Normally 1.14 works for everything. Later versions have more features but may add bugs too
Hi, I'm interested in ULX3S.
ULX3S page in Crowd Supply says "Orders placed now ship Aug 19, 2022", can I buy ULX3S from Crowd Supply now?