update 4ft4 submodule & 4ft4_top

connect rom in & ram out to gpio.

add LA probes for halt and reset.
3 files changed
tree: c429d5dc4d85a95c9d15af132e6e9388c1ee1df7
  1. .github/
  2. def/
  3. docs/
  4. gds/
  5. lef/
  6. mag/
  7. maglef/
  8. openlane/
  9. signoff/
  10. spi/
  11. verilog/
  12. .gitignore
  13. .gitmodules
  15. Makefile
  16. README.md

Caravel 4ft4

4ft4 is a clone of the MCS-4 architecture (4004 CPU, 4001 ROM, 4002 RAM), with a wishbone backdoor interface to the “ROM” and the RAM that enables loading a program for execution and inspecting/modifying the RAM.

This is an integration of 4ft4 into the caravel harness, with the 4ft4 wishbone backdoor interface connected to the caravel management processor.

License information

caravel_user_project and modifications: Apache 2.0. The original caravel_user_project that this is based on is https://github.com/efabless/caravel_user_project.

4ft4: MIT.