BoxLambda is a project that creates a retro-style FPGA-based microcomputer from open-source components. The microcomputer serves as a platform for both software and RTL experimentation.
BoxLambda is a software-hardware crossover project, providing opportunities for experimentation on both the FPGA RTL side and the software side.
- Targets the Arty-A7-100T FPGA development board.
- Ibex RISC-V core with machine timer and hardware interrupt support.
- Stable low-latency access to internal memories and registers. Stable and documented instruction cycle counts.
- DDR3 external memory access through the Litex memory controller.
- OpenOCD-based debug access on FPGA and Verilator.
- VERA-based VGA graphics: 2 layers tile or bitmap mode, 2 banks of 64 sprites, 128KB Video RAM, 256 color palette.
- Dual YM2149 PSG Audio.
- SD Card Controller and FatFs File System.
- 24-pin GPIO, UART, SPI Flash Controller, I2C Controller.
- Real-time Clock and Calendar (RTCC) support.
- USB HID Keyboard and Mouse support.
- Picolibc-based standard C environment.
- DFX Partial FPGA Reconfiguration support.
- Test application suite covering all SoC components, running on both FPGA and Verilator.
- Linux CMake and Bender-based Software and Gateware build system.
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Create a sandbox for experimenting with software and FPGA gateware:
- It should be easy to jump in and do something: create, hack, tinker.
- Simple Enough for One Person: A motivated individual can develop a solid understanding of the entire system, including both software and hardware.
- Deterministic Behavior: The duration of operations such as internal memory or register access must be predictable by design.
- Self-Contained Run-Time Environment supporting high-level interactive and low-level systems programming.
- Create a Modular Architecture allowing for a mix-and-match of software and hardware components. Optionally, support Partial FPGA Reconfiguration.
- It should be easy to jump in and do something: create, hack, tinker.
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Target Hardware: Digilent's Arty-A7.
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The computer supports the following peripherals:
- USB HID Keyboard
- USB HID Mouse (optional)
- USB HID Joystick (optional)
- Real-Time Clock and Calendar (optional)
- Serial port
- SD card storage
- Flash Memory storage
- VGA Display
- Audio output
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Sound and graphics support retro-style 2D demos and gameplay.
- Infrastructure (build system, etc.): Complete.
- Gateware: Complete as pictured in the Block Diagram. Meeting requirements, but IRQ Latency yet to be analyzed.
- Software: Early stage development.
- Source Code: https://github.com/epsilon537/boxlambda/
- Project Blog: https://epsilon537.github.io/boxlambda/
- Project Documentation: https://boxlambda.readthedocs.io/en/latest/