journal 2026-05-05

Banked lower-memory conflict counters

P104 kept the memory implementation single-port but added a word-interleaved four-bank accounting model underneath the Harvard I/D service counters.

The BusyBox shell smoke reached P104-FILE-OK. The important number: when instruction and data both wanted lower memory, 20,564,832 cycles mapped to different banks and still serialized through the current shared port. That is 71.40% of simultaneous I/D lower-memory demand.

Result: PASS for RTL simulation and shell profiling. Hardened layout: NOT RUN.