Simple SoC

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Description

A very basic, custom SoC softcore


Primary git repo: on github

Specs/Design: on github as well

We'll merely keep a meetup log and notes here, important stuff will be stored in One Single Repo (tm), next to the code :)


(Final?) working implementation, with VGA output and debugger

https://www.youtube.com/watch?v=YfNVco7CpEU

Meetup Log

2013/09/11 - September reunion

  • Discuss and improve specs a bit
  • Update documentation and C# ref. implementation
  • forked from Programmable Logic Lessons to Simple SoC

2013/09/18 - Let there be code

  • Debugged & Finished sdlcore implementation

2013/09/25 - Verilog at last

  • Spec now has vsync
  • Reviewed sdlcore code
  • Hacked together some very basic Verilog

2013/10/02 - Howdy Simulator

  • Implemented ram
  • Added delays for ram

2013/10/09 - Howdy Simulator, for real

  • debug, debug, debug, and simulate
  • Implemented more state logic
  • cpu mostly works, needs some more opcodes!

2013/10/16 - How about conditions?

  • Implemented beq, bga, bgt, jr, draw, fixed write16, read16
  • wired up vram (resized to 2bpp because it doesn't fit)
  • added vga output, but it is glitched/buggy

2013/10/23 - We love glitches

  • Fixed VGA, centered image, still outputs corrupted data though
  • vram resized to 256x256x3 in order to fit

2013/10/30 - Corrupted Pixels

  • Had no luck actually locating the vga corruption bug
  • simulator results and simpler test cases seem to work fine
  • implemented wait

2013/11/13 - Differential debugging

  • Investigate serial communications
  • Try out UART sample
  • draft out ICE spec

2013/11/20 - Want some ICE?

  • *almost* implemented the UART
  • We have some pin collisions on clock vs dcm vs io-standards per ban

2013/12/04 - Clocks and IO

  • Worked around the IO/DCM issues
  • WIP on the ICE implementation

2013/12/11 - Debuggable Hardware

  • Work on the ICE implementation

2014/01/22 - ICEful modules

  • Modularization, refactoring

2014/01/29 - Making it work once more

  • Get the modularised code back into working state
  • implement some of the ICE state machine

2014/02/05 - Debugger Integration

  • implement some of the ICE state machine
  • have it talk nicely with the debugger
  • -> We got VGA writes working!

2014/02/26 - Wait States

  • Add wait states for ICE & module integration on the cpu
  • have it talk nicely with the debugger

Resources