Prebuilt FPGA Bitstreams
Ready-to-program bitstreams for supported boards.
VCU-118 (Xilinx Ultrascale+)
Microwatt v0.1 - Native Build
Specifications:
- CPU: Microwatt 64-bit PowerPC
- Clock: 125MHz
- Memory: 2GB DDR4
- Peripherals: UART, GPIO LEDs
- Linux: Boots to prompt
Download:
wget https://powercommons.org/downloads/microwatt-vcu118-125mhz.bit
wget https://powercommons.org/downloads/microwatt-vcu118-125mhz.bit.sha256
Program:
openocd -f vcu118.cfg -c "init; pld load 0 microwatt-vcu118-125mhz.bit; exit"
Serial console: /dev/ttyUSB1 @ 115200 baud
Microwatt + LiteX SoC
Specifications:
- CPU: Microwatt
- Clock: 100MHz
- Memory: 256MB DDR4
- Peripherals: Ethernet, UART, SPI
- Linux: Full networking stack
Download:
wget https://powercommons.org/downloads/litex-microwatt-vcu118.bit
Program:
litex_term --kernel=zImage --kernel-adr=0x00000000 /dev/ttyUSB1
Arty A7-100T (Xilinx 7-Series)
Microwatt Minimal
Specifications:
- CPU: Microwatt
- Clock: 50MHz
- Memory: 256MB DDR3
- Peripherals: UART
- Status: Hello World working
Download:
wget https://powercommons.org/downloads/microwatt-arty-a7.bit
Program:
openocd -f arty_a7.cfg -c "init; pld load 0 microwatt-arty-a7.bit; exit"
Coming Soon
A2O Core (VCU-118)
PowerPC A2O out-of-order core with 4-way SMT.
ETA: Q2 2026
Build Information
All bitstreams built with:
- Vivado: 2025.1
- LiteX: Latest stable
- Build date: Included in filename
Example: microwatt-vcu118-125mhz-20250930.bit
Programming Tips
Persistent Flash Programming
Program to SPI flash for persistence across power cycles:
VCU-118:
vivado -mode batch -source flash_program.tcl
Arty A7:
openocd -f arty_a7.cfg -c "init; pld load 0 bitstream.bit; jtagspi_init 0 bscan_spi_xc7a100t.bit; jtagspi_program bitstream.bit 0x0; exit"
Verify Programming
Check LEDs on board:
- LED0: Power good
- LED1: PLL locked
- LED2: UART TX activity
- LED3: Heartbeat (toggling = CPU running)
Checksums
Verify integrity:
sha256sum microwatt-vcu118-125mhz.bit
# Should match .sha256 file
License
Bitstreams are provided under the same license as source (Apache 2.0 or GPL-3.0). See repository for details.
Issues
Bitstream not working? Check:
- Correct board variant (VCU-118 vs VCU-128, Arty A7-35T vs A7-100T)
- Cable drivers installed
- Troubleshooting guide