News of Lethe and Dhar

Newest entries at the top.

• 2024-09-28: Much progress on the CHASM simulator. Firmware can now load and display a full-screen BMP image without any errors—but coding in assembly is error-prone and slow. Redirecting full attention toward designing the Dhar runtime.
• 2024-09-16: CHASM spec updated. Removed unfashionable BCD support and replaced it with rudimentary string handling.
• 2024-09-15: Removed links to (most) incomplete pages, and added theory piece on Buzzword Pinnacle.
• 2024-09-14: chas assembler now on GitHub.
• 2024-09-14: CHASM spec updated. Many new instructions. New instruction format for arithmetic operations.
• 2024-08-25: CHASM spec updated. Complete except for specs of ROM, power control interface, and vector processor.
• 2024-08-22: After spinning my wheels staring at the grotesque complexity of a modern bootloader, I've decided that building an interim VM from scratch, without legacy cruft, and tailored to my idiosyncratic expectations, is actually a shortcut to getting things done, rather than a distraction. Accordingly, specifications for the CHASM virtual machine and the PETRA filesystem have been posted. As of this writing, CHASM is not meant to be a final destination; unlike the JVM or Lisp Machine ISA, it's a RISC-adjacent register machine that conforms to the basic attributes of normal commercial ISAs. Automatic conversion of most programs may even be possible.
• 2024-07-22: Most of this site is now up. Notable omissions include the Hekarti, Yutani, Workspace, and Applications pages. Most of the content is on the Dhar sibling site.