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Standard Library

Helper macros from asm/std.asm. Include them after cpu.asm/ext.asm to get simple data routines.

MEMCPY

  • Syntax: MEMCPY i len srchi srclo dsthi dstlo
  • Inputs: i loop counter (start at 0), len stop value, srchi:srclo source pointer, dsthi:dstlo destination pointer.
  • Behavior: Copies bytes from source to destination until i == len. Both pointers are incremented with INC16. Restores i each iteration via push/pop.
  • Scratch: uses stack to save i; flags from CMP, INC, INC16.

STRCMP

  • Syntax: STRCMP i j srchi srclo dsthi dstlo
  • Inputs: srchi:srclo first string pointer, dsthi:dstlo second string pointer.
  • Outputs: i receives 0 when strings match, 1 otherwise.
  • Behavior: Walks both zero-terminated strings byte-by-byte. Returns early on mismatch, or when a 0x00 terminator is reached on both sides.
  • Scratch: uses i, j, flags from CMP, CMPI, JZR/JNZR, and increments addresses with INC16.