HDGL SUBSTRATE — USB PROGRAM LOADER
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Programs are plain text files written to LBA 18 of the USB drive.

At boot, the substrate:
  1. Runs the axiom (Omega emerges as phi, genome settles)
  2. Loads the text at LBA 18
  3. Executes it as a program
  4. Returns to normal substrate operation when done

WRITING A PROGRAM TO USB
  dd if=myprogram.txt of=/dev/sdX bs=512 seek=18 conv=notrunc

INSTRUCTION SET (one character per instruction)
  F    run the Fibonacci integer ladder (never-ending, any key stops)
  f    same as F (existing substrate fib mode)
  o    load Omega (phi) into accumulator
  n    load 1 into accumulator
  t    apply T(x) = 1 + 1/x to accumulator
  p    print accumulator value
  +    accumulator += 1
  -    accumulator -= 1
  *    accumulator *= accumulator
  /    accumulator = 1/accumulator
  0-9  load digit into accumulator
  s    print full substrate state (Omega, Lambda, Ether, Genome)
  l    mark this program as looping (repeat from start)
  L    mark loop point here (repeat from this position)

Whitespace, newlines: ignored.

EXAMPLE PROGRAMS
  fib.txt:    F
              (never-ending Fibonacci integer ladder)

  phi.txt:    ntp l
              (seed=1, T(1)=2, print, loop -> converges to phi)

  orbit.txt:  osp l
              (load Omega, print substrate state, loop)

FUTURE
  As we add instructions, programs grow in expressiveness.
  Next: integer arithmetic, conditionals, I/O.
  Eventually: a self-hosting system built from text files on USB.
