Tone+FX 4.0a - DELAYS (WRMZ/GRAINZ) + CPU pass

Tone+FX 4.0a — DELAYS (WRMZ / GRAINZ) + CPU pass

The Tone+FX suite (now twelve pages) plus a new buffer-FX module: a
dedicated mono delay line that serves two modes — WRMZ (a modulated delay)
and GRAINZ (a cloud of three drifting taps on the same line) — edited on one
DELAYS page. Four OS files, two hosts: the Digitone mk1 / Keys (OS
1.43, 1.44) and, through gdeo607's community port, the Digitakt mk1 (OS
1.53, 1.54).

This is the first release built on the ToneFX-BufferFX line, so it also
carries a CPU/headroom pass over the whole suite (see New in 4.0a).

Digitakt mk1 (community port by gdeo607) is now on 4.0a too — the same
DELAYS module and CPU pass, plus its own fixes: encoder travel, the master-page
cycle limited to the master-FX pages, and a repacked per-pattern store. Source
mirrored under
DIGITAKT PORT/.

Install

Each file is the whole suite + DELAYS for one OS; none includes the core.

file	device	OS	required core
tonefx-4.0a.elemod	Digitone mk1 / Keys	1.43	core-dn1-4.0.elemod
tonefx-4.0a-os1.44.elemod	Digitone mk1 / Keys	1.44	core-dn1-4.0-os1.44.elemod
tonefx-4.0a-dt.elemod	Digitakt mk1	1.53	core-4.0.elemod
tonefx-4.0a-dt-os1.54.elemod	Digitakt mk1	1.54	core-4.0-os1.54.elemod

Install the matching core (elekloader provides it), tick the core and tonefx,
set the OS version tag and BUILD FIRMWARE; flash the .syx with Transfer.
Or use tools/build.ps1 / tools/build.sh. No firmware is included.

New in 4.0a

DELAYS — WRMZ / GRAINZ (one delay line, two modes)

A DELAYS page (kind 11) after the FX chain. D switches the mode; the
rest of the encoders edit the active mode's six parameters. True-bypasses when
off (the line is untouched). Mono wet, mixed into both channels (the dry
stays stereo — widen externally).

• WRMZ — a modulated delay: TIME, FB (feedback, capped at 0.80), TONE
  (one-pole damping), MOD (depth), RATE (0.1–3.0 Hz wow/flutter), MIX.
• GRAINZ — a grain-ish cloud: three drifting, interpolated taps off the
  same line — DENS (drift), SIZE (tap spacing), PIT (parked), SPR (spread), FB,
  MIX.

Per-pattern store DGX3 v1 (15 params); MIDI CC 80–87. The suite's
output ceiling and meter still run last, so the chain is
ring → EQ → crush → fold → wave → WRMZ → ceiling → meter.

CPU / headroom pass

• eMAC mode switch hoisted to once per block (digictl_macsr_begin/_end,
  ev_render_out order 49/74) instead of once per handler. On hardware an
  eMAC-off A/B idled lower but ran worse while processing, so the eMAC
  is kept.
• Wave lines s16 (were 24-bit) with the interpolation done in the line's
  scale — halves the wave delay lines' DDR traffic and RAM.
• Wave wv_flush spike fixed — the one-time whole-line clear (2564 stores)
  on a mode change is gone (only FLAN's own feedback line is cleared); the
  per-mode worst case now equals its p99 (e.g. SHFT worst +9,984 → +5,491
  cycles/block).
• UI redraw cap — animated pages redraw at ~5 Hz (was ~10), and a page whose
  section is off is static.
• Size-optimised build (-Os): .run 34,398 → 26,018 (−24 %), for i-cache.

Tested

• Both builds compile clean and imports nothing — Digitone 1.43 / 1.44
  (.run 26018, .bss 47246, 11 sites) — each links as core 4.0 > tonefx 4.0a
  and patches byte-for-byte against its own stock file.
• Emulator (Digitone dn1): boots, settles, dsp_running=2; all twelve pages
  incl. DELAYS; live diag (WRMZ + GRAINZ, real SSI renders) 0 faults;
  _probe_mix 0 clips. The OS 1.44 build is patch-checked; digiemu cannot
  settle 1.44.
• CPU ledger and the A/B write-ups: source repo
  docs/OPTIMIZATION-ROUND.md §10–§12.

Known issues

Same as 3.5r — PAGE can still jump some FX levels, PITCH can fire on a
note-off, SHFT is deliberately lightweight, PERFORM trig LEDs do not
light. The DELAYS page's GRAINZ PIT control is parked (the taps read at rate
1.0). Full, current list in the README's "Known bugs / future fixes".