Arduino core extensions for FPGA-based 32-bit MIPS and RISC-V soft CPU cores (f32c).
We have preliminary Boards Manager support. In File->Preferences->Additional Boards Manager URLs enter:
http://www.nxlab.fer.hr/fpgarduino/package_f32c_core_index.json
Select pull down menu Tools->Board->Board Manager and instal FPGArduino (cca 100MB).
Upgrading
Before upgrading to new version, boards manager cache has to be manually removed by deleting hidden directory 'packages'. If install is attempted with old cache, it will fail with CRC error.
windows cache: .../Arduino15/staging/packages (use Find files)
linux cache: ~/.arduino15/staging/packages
Delete packages directory, then remove/install from boards manager.
To upload some bitstreams OpenOCD may complain about libusb drivers. libusb is common on linux. To install libusb on windows, easiest way is with Zadig http://zadig.akeo.ie Options->List All Devices Select usb serial device, select driver WinUSB and click install. Zadig is not needed for ftdi based boards with own uploader like ULX2S or FleaFPGA. Zadig can have some issues with ftdi drivers for windows 10.
Manual install: Copy or symlink this to existing arduino directory (versions 1.6.0 and newer), close the Arduino IDE, open it again and new FPGA boards, progammers and examples should appear under pull down menus:
tools->boards->...new mips and riscv boards..
tools->programmers->...ujprog openocd etc...
file->examples->f32c->...
file->examples->...RCswitch...Adafruit GFX/SSD1306..
We had to do small modifications of original examples for AVR-specific or hardware-dependent stuff in order to get them running out of the box on f32c.
Source tree arduino/hardware/fpga contains complete arduino core for unified MIPS and RISC-V achitecture support. Only this directory is needed to be copied to your existing arduino-1.6.x tree. Core can work alone without libraries and examples.
The core comes without GCC for MIPS/RISC-V and tools to upload binary and FPGA bitstreams (ujprog, openocd, JTAGs).
Precompiled binaries for linux and windows with GCC MIPS and RISC-V can be fetched and installed separately, see http://www.nxlab.fer.hr/fpgarduino for further instructions.
There are some short scripts and patches to build GCC from source in https://github.com/f32c/f32c/tree/master/src/compiler
Blink led :)
Serial (over usb-ttl adapter, some boards need it external)
Timer (millis(), micros() - 32-bit CPU core clock counter, glitch-free, good for realtime)
GPIO (digitalWrite(), digitalRead())
Interrupts (MIPS only, attachInterrupt() gpio rising/falling edge, timer)
PWM (analogWrite(), analogWriteResolution(), analogWriteFrequency())
Fade (PWM) works on 2 output pins (LEDs).
Software SPI (bitbang, Adafruit OLED library)
Hardware SPI (SD card library)
Software I2C in master mode (SoftwareWire library)
OLED displays SSD1306 compatible (Adafruit SSD1306 library, SPI and I2C)
PID (Proportional-Integral-Derivative controller, fast response, hardware math accellerated, tested on high speed DC motors with encoders)
433.92 MHz transmitter (RCswitch library, Home automation, Remote relays, Garage doors).
FM RDS transmitter 87-108 MHz (RDS message displayed on radio, but PCM sound supported only on ULX2S)
RHT11 Temperature/Humitidy sensors have been reported to work.
SRAM in 8-bit mode (FleaFPGA Uno) and 16-bit mode (ULX2S)
SDRAM in 16-bit mode (Altera DE0 nano and Scarab MiniSpartan6+)
VGA/HDMI/DVI bitmap needs large RAM (SRAM or SDRAM ULX2S, FleaFPGA Uno, Scarab Minisprtan6+, Altera DE0 nano). However some test picture and reduced bitmap can be produced with BRAM-only boards. It can run asynchronous from CPU clock. A new textmode is implemented to FleaFPGA and under construction for other boards.
TV Framebuffer with composite video output displaying SRAM content tested only on ULX2S, should work on any other capable of 81.25 MHz CPU and 325 MHz pixel clock. Composite video currently must run synchronous with CPU clock.
DMA works only on boards that support SRAM or SDRAM.
PCM sound depends on DMA. PCM outputs PWM for headphones and FM for reception on 87-108 MHz radio.
Text-to-Speech library TTS depends on PCM. TTS library could be converted to use a simple tongenerator then it will not depend on PCM)
DCF77 transmitter depends on PCM. A proof of concept to adjust longwave RF clocks.
Analog inputs work on FleaFPGA Uno board thanx for contribution.
Pullup digital input control works on FleaFPGA Uno board (it would work on any board but 2 hardware pins must be dedicated for 1 GPIO pin, one of them having pullup resistor)
Hardware I2C slave is not planned soon, as f32c is expected to be an I2C master in most cases.
There's SoftwareWire I2C master which works because F32C is fast enough and has high resolution 32-bit timer.
DDR memory is currently not supported. This includes all types, DDR, DDR2, DDR3. Support for it should be possible because FPGA vendors are providing some proprietary solutions for a range of selected memory chips.