8.8 KiB
ULX3S Manual
Connectors
US1 Main micro-USB for power, program and communication.
All onboard hardware can be programmed or reconfigured
over US1: FPGA, FLASH, WiFi, RTC.
US2 Auxiliary micro-USB connected directly to FPGA pins
for experimenting with user-defined USB cores.
Board provides power to US2.
Board can't be powered from US2.
GPDI Plug for cable to digital monitor or TV,
4 TMDS+- video
1 HEAC+- ethernet and audio return
SDA,SCL I2C (DDS EDID)
CEC remote control
+5V supply to enable plug-in detection
AUDIO 3.5 mm jack with 3 channels for earphones
and digital audio or composite video (analog TV)
Suitable cables are 3.5mm to 3-RCA (cinch)
Red-White-Yellow for iPhone/iBook/NOKIA.
Sony cables are the most popular and look identical
but are not suitable, they have GND at Ring2!
Tip: Left analog audio
Ring1: Right analog audio
Ring2: Digital audio SPDIF
Sleeve: GND
OLED 7-pin 2.54 mm header OLED1 for SSD1331 SPI color OLED
pinout: CS DC RES SDA SCL VCC GND
JTAG 6-pin 2.54 mm header J4 for external JTAG programmer
pinout: 3V3 GND
TCK TDI
TDO TMS
GPIO 40-pin 2.54 mm double-row connectors J1 and J2 with
total 56 GPIO pins at 3.3V logical level.
Pins can be used as 56 bidirectional single-ended
or 28 bidirectional differential pairs.
J1 pins marked 9-13 are shared with WiFi (PCB v1.7)
J2 pins marked 14-17 are shared with ADC.
Pin-compatible with 4 PMOD connectors (GND and 3.3V power
are on the right place)
J1-J2 distance suitable to be plugged into triple
protoboard using a single row of J1/J2.
J2 has also 5V IN/OUT (be careful, digital pins are 3.3V).
SD Micro SD card, all signal pins are routed to FPGA and
shared with ESP-32
ESP32 Placeholder to solder ESP-32 WROOM module.
ESP-32 can provide web interface for uploading bitstream
into FPGA and its config FLASH.
Warning on PCB v1.7 ESP-32 must be isolated from all SD
card pins otherwise ESP-32 won't boot no matter if
SD card is inserted or not.
Power
Plug US1 into PC or USB charger and board should power up.
Initial voltage rise at USB 5V line will trigger board powering up and holding the power.
USB-serial chip FT231X will always be powered from 5V USB on PCB v1.7. The board has switching voltage regulators which can be turned off to reduce power consumption.
Green LED D18 behaviour is the "Power LED". Green LED ON will keep board powered up. By factory default, when USB-serial chip is enumerated by PC, Green LED will turn ON. Normally when board is plugged into USB charger Green LED may shortly blink and stay OFF, but board will keep being powered.
Board PCB v1.7 must be hardware patched to be able to reliably enter shutdown mode. (It will keep waking up).
RTC without battery will keep powering up the board as factory default. 3V battery CR1225 and configured RTC chip is required for the board to enter shutdown mode. There are several ways to wake up the board:
1) Press BTN0
2) Re-plug US1 micro-USB cable
3) RTC ALARM (using PCF8523 arduino example)
4) Turn on Green LED D18 (using ftx_prog or libftdi)
Just a short pulse at RTC (ALARM INT1 shorly pull down) or Green LED shortly going HIGH is enough to wake up the board.
There is SHUTDOWN pin where FPGA can turn OFF the board. This pin is not correctly routed on PCB v1.7 and needs hardware upgrade to make it work.
On J2 connector there are 2 pins for 5V external power input and output. They are located on top right, near pin labeled 27 and US2 connector. Power is unidirectionaly routed using schottky diodes.
Powering only from 3.3V is not possible because switching regulators need 5V to generate 2.5V and 1.1V.
Switching regulators use ferrite core coils L1,L2,L3 which can saturate at magnetic fields above 0.3T. Never approach neodymium magnets near powered board.
Programming
Use ftx_prog to change product/manufacturer name of FT231X chip:
ftx_prog --manufacturer "FER-RADIONA-EMARD"
ftx_prog --product "ULX3S FPGA 45K v1.7"
Optionally you can change "45K" to "25K" or "12K" in regard with FPGA chip size. Re-plug the USB and it will appear as new name which can be autodetected with USB-serial JTAG tool.
Use Emard's fork of Xark's FleaFPGA-JTAG tool. This tool accepts VME format bitstreams which write bitstream to the FPGA SRAM or onboard SPI FLASH chip. When generating FLASH bitstream, follow the Lattice TN02050 document: "Programming External SPI Flash through JTAG for ECP5/ECP5-5G" section: "6. Programming the SPI Flash with bitstream file using Diamond Programmer" and select FLASH chip type as:
Family: SPI Serial Flash
Vendor: Micron
Device: SPI-M25F32
Package. 8-pin VDFPN8
When it creates VME file, pass it to FleaFPGA-JTAG argument and wait 5-10 minutes, it's not particulary fast but it works.
FleaFPGA-JTAG bitstream-flash.vme
External JTAG like FT2232 can be connected to JTAG header and it will program SRAM and FLASH at maximum speed possible. Even Diamond programmer can use any FT2232 module as a native programmer, with a little help - it will work after first bitstream is programmed over FT2232 with openocd.
Openocd accepts SVF files, everything applies the same as for VME files
ddtcmd -oft -svfsingle -revd -if ulx3s_flash.xcf -of bitstream.svf
Programming and flashing from ESP-32 web interface is convenient (device independent) and much faster than FT231X but still not as fast as FT2232. It also accepts SVF files, only you need to limit SVF command size to max 8 kilobits "-maxdata 8" because ESP-32 doesn't have enough memory to buffer entire bitstream.
ddtcmd -oft -svfsingle -revd -maxdata 8 -if ulx3s_flash.xcf -of bitstream.svf
To start using ESP-32 first you need to compile and upload "passthru" bitstream, which can be found in f32c project Using FleaFPGA-JTAG or external JTAG programmer to upload it. "Passthru" butstream uses FPGA to route lines from USB-serial to ESP-32.
Then you need to install Arduino and its ESP-32 support, and install Emard's library LibXSVF-ESP, required library dependencies and ESP-32 SPIFFS uploader Version "ESP32FS-v0.1.zip" worked for me.
In Arduino boards manager select this ESP-32 board:
DOIT ESP32 DEVKIT V1
Select "Examples->LibXSVF->websvf" and optionally change its default ssid/password. Compile and upload the code by clicking "Sketch->Upload", check reports on lower terminal window, successfull upload will finish with this:
Hash of data verified.
Leaving...
Hard resetting...
Then upload the web page content to ESP-32 FLASH filesystem, at websvf window click "Tools->ESP32 Sketch Data Upload". successful upload will finish with same as above.
Connect to ESP-32 WiFi (it will either connect to your local WiFi or become access point with default ssid=websvf password=12345678).
In web browser open upload page "http://192.168.4.1" (If it connected as a client, IP address will vary depending on your local network and you need to find it using WiFi access point web interface, ARP, NMAP, or by sniffing it). On the ESP-32 page you should see something like:
Select SVF File or use minimal or svfupload.py
[File] File not selected
[Upload]
[0% ]
Navigate file selector to bitstream.svf file, it will show its size in KB. Then click "Upload", progress bar will run from 0% to 100% in few seconds (if it's SRAM upload) and bitstream will be started. FLASH can also be written from web iterface it takes 2-3 minutes. Also on the web interface there's available for download a small python commandline upload tool.
Note that FPGA can enable or disable ESP-32 module. If ESP-32 is disabled by newly uploaded bistream, some alert window will pop-up after otherwise successful upload because ESP-32 cannot close HTTP session properly. To make it go smooth, in the bitstream make FPGA pin "wifi_en" as input (HIGH-impedance, pull up).
Technically, ESP-32 can be loaded with such a code that permanently holds JTAG lines while FPGA can at the same time have in FLASH a bitstream that permanenly enables ESP-32. Such combination will preventing JTAG from working so ULX3S board may become "Bricked". There is jumper J3 to disable ESP-32, its left of SD card slot. Note boards PCB v1.7 need upgrade for this jumper to work correctly.