32 bit EON cpu implemented on tinyfpga BX. The internal clock frequency is 16MHz, I2C bus is about 400Khz and SPI bus is about 1MHz.
I suggest you to consider first eonduino. Easier to build and same hardware. One important difference: tinyfpga BX is 3.3v (avr is 5v).
The source has a SOC module, which implements: uart, i2c bus, spi bus, l2 memory cache, eeprom driver, sram driver and a debug module.
The core cpu is implemented in coreZ0. It's a pipelined, single issue, out of order execution, commit in order design.
Prerequisites:
- eonrom.img from eonrom
- iverilog/vvp
- gtkwave (optional)
- yosys
- nextpnr
- icepack
- tinyprog
- a serial terminal emulator. I use picocom, but any other will work.
to build emulator and wave file, just type make
to build fpga image, type make /tmp/hardware.bin
and finally type make tinyfpga && make com to enjoy your system !