Provide a directional pair of extension boards that carries one axis’s STEP, DIR and ENABLE commands from a Smoothieboard V2 Gadgeteer Y socket to a remote external stepper drive over three balanced twisted pairs.
Baseline documentation snapshot: 2026-10-11, before the requested connector/protection/usability revision program. New revision features require their own reviewed source and qualification evidence.
This page documents an unqualified engineering study, not a released or tested product. Saved CAD, renders and automated checks do not establish a safe assembly, compatible cable, firmware support or a usable current rating.
Board-specific qualification limits: HOST30/REMOTE52findings,REMOTE5opens;56blank MPNs,host/common-mode/fault/physical open.
The exact connector orientation, pin mapping and supply ownership must be taken from the selected revision’s schematic and connection specification. Do not infer wiring from the connector shape.
Power off before connecting or changing jumpers. Verify pin 1, signal direction, supply voltage and ground at both ends of every cable. A mechanically fitting connector is not proof of electrical compatibility. If a host pin mapping or current allocation remains unresolved in the design record, do not connect the board until it is resolved.
The following are specification requirements or study assumptions; they are not measured operating ratings. A newer selected-revision note takes precedence over historical draft options.
Exhaustive current pair review: v27pair retains dedicated channels/rated terminations/conditional capacitor preferences,no successor.59refs/140selected/978role hashes;56exported MPNs blank. HOST30/REMOTE52findings,REMOTE5opens and host/fault/physical gates remain open.
Use the configuration and firmware contract for the exact selected revision. Do not copy another module’s socket assignments or assume that an unused pin is available. First-article work must verify source selection, reset/unplug behavior, cable orientation and the actual load or sensor interface before normal operation.
The following are requirements for the next design iterations; this page does not claim they are already fitted:
Documentation route: smoothieware.org/extensions/differential-step-dir-en-extender.
The 2026-10-11 upgrade program has saved additional candidates v28, v29, v30. These studies preserve the historical design described above. Their connector, LED, mechanical and protection changes are revision-specific and remain unqualified.
See the per-board changes, failures and remaining work and mandatory family specification. Use the source hash and native check for the exact candidate being reviewed; do not infer hardware ratings from a rendered population.
The three additional revisions are v28, v29, v30. They are engineering studies; saved CAD and renders do not release the hardware. The latest candidate is described below. Older baseline notes above remain historical.
d2be2438b6e510ee1dbda3fba7e59d2a3bc454153b7abd11e65cf88c974d2e2e.e621304d60570f67cb04d12eec361d8040894bf0418e2b83f1e82b49bfb794e0.Applicable protection, current-path, thermal, pinout, cable access and physical tests remain open wherever the linked board record has not verified them. A zero native-error count does not close those gates.
The remote third additive candidate includes a TPS26600 automatic-retry input eFuse, OV cutoff with separate raw-side indication, reverse cutoff with a floating blinking timer, soft start and individual LED links. Protection returns to SIGNAL_GND; SHIELD remains separate and the host circuit is preserved. Signal power sequencing, failsafe behavior, transients and hardware qualification remain open. Native routing remains incomplete; see the source-bound readback and per-revision NATIVE-CHECKS.md.
The current retained revision is V31; the earlier readback above is historical. Uppercase version labels and documentation annotations were refreshed without changing the circuitry, placement, routing, zones, mechanics or rules. Source-bound candidate review records every role, unchanged native diagnostic categories, current models, views and manufacturing hashes. This remains a partial engineering candidate with fabrication release false.
Host: 14 clearance errors, zero opens, 9 warnings. Remote: 46 errors including 31 opens, 36 warnings. Both normal packages contain 12 inspected views and 91 resolved model entries. Complete documentation URLs remain readable; host edge proximity and title/cable-tie crowding, remote back annotation overlap and front low contrast remain explicit limitations.
Short-title Montserrat conversion is deferred after warning-increasing retained trials. Native parity/ERC findings are zero and settings are unchanged, with no ignored rule categories or exclusions. This does not verify electrical operation, current/thermal limits, isolation, protection behavior, timing, mounting or assembly. All existing pin maps and power/cable safety limitations on this page still apply; no price or area-saving claim is made.
Both physical boards passed independent source/history/model/export checks and all12views were visually reviewed with complete framing. Registered as a partial annotation improvement: remote retains46layout errors including31unrouted connections and36warnings; host retains14clearance errors and9warnings. Both schematics have zero errors. Current labels and complete documentation URLs are retained; crowded and component-occluded inherited labels and title font consistency need further work. Electrical geometry and rules are unchanged. Physical and fabrication qualification remain open.
The V31 host receives trusted Gadgeteer power and has no added generic input-protection annex to remove. The remote accepts a user-wired 18–50 V screw-terminal supply, so its compact input protection is retained. The host remains 60 × 40 mm and the remote 60 × 60 mm. No CAD revision is added for this classification review; the existing host clearance errors and remote layout errors/open connections remain unresolved, and fabrication release remains false.