c4f33e1c9d
- 99-retro-usb-permissions.rules renamed to 90-retro-usb-permissions.rules
- 91-retro-usb-latency.rules: udev rule to enforce low latency for FDTI USB UART
- 92-retro-usb-persistent.rules: udev rule for persistent device names
- Note:
- for all FTDI USB-UART it is essential to set them to `low latency` mode.
That was default for linux kernels 2.6.32 to 4.4.52. Since about March
2017 one gets kernels with 16 ms default latency again, thanks to
kernel patch 9589541. For newer systems it is essential to install the
udev rule which automatically sets low latency.
w11: PDP 11/70 CPU and SoC
Overview
The project contains the VHDL code for a complete DEC PDP-11 system: a PDP-11/70 CPU with memory management unit, but without floating point unit, a complete set of mass storage peripherals (RK11/RK05, RL11/RL02, RK70/RP06, TM11/TU10) and a basic set of UNIBUS peripherals (DL11, LP11, PC11), and last but not least a cache and memory controllers for SRAM and PSRAM. The design is FPGA proven, runs currently on Digilent Arty, Basys3, Nexys4, Nexys3, Nexys2 and S3board boards and boots 5th Edition UNIX and 2.11BSD UNIX.
For more information look into:
- w11 project home page and blog
- change log and installation notes
- guides to build bit files and test benches with Xilinx Vivado and Xilinx ISE
- guides to run test benches and to boot operating systems
- known issues general and w11a CPU
A short description of the directory layout is provided separately, the top level directories are
| Directory | Content |
|---|---|
| doc | documentation |
| rtl | HDL sources (mostly vhdl) |
| tools | many tools |
Note on freecores/w11
The freecores team created in 2014 a copy of almost all OpenCores cores in Github under freecores. This created freecores/w11 which is outdated and not maintained. Only wfjm/w11 is maintained.