; CH08 r007: isolate BRK at the card-side idle scan, with firmware fallback.
; Reuses frozen keystone / BOOT firmware text path.
; r001 shell menu and four diagnostic routes emulator-observed.
; Keystone guest is NEW, not yet assembly- or runtime-verified.
; After external assembly/observation, integrate one donor at a time.
 ; BRK r005/r006 trampoline at 30C0 retired: during firmware dispatch
 ; C-ROM is physically selected, so 30C0 fetches C-ROM data, not card code.
 ; For BRK during an unavoidable C-ROM call, BOOT ROM 0.02a uses the
 ; native restart vector 0000. This is a protective COLD fallback,
 ; not the warm-return contract. Warm BRK must be caught card-side.
; CH08 r008 experiment-only marker.
; ROM2:2E00..2E01 = FF FF; RAM1:2E00..2E01 is dedicated probe.
; The marker is never executable code and is copied on CH08_COLD only.
; Do NOT place the RAM target in the firmware bridge, stack or Life mirror.
        ORG     &H2E00
C8_MARK:
        DB      &HFF,&HFF