Ground Plane Setup Instructions
Worked for 39 mins 59 sec
I moved the USB/CH340 section to improve routing and reran autoroute.
What changed:
- Repositioned J1/J2 with U3/U4 and local USB passives for cleaner USB D+/D− escape.
- Removed stale USB-area traces/vias before routing.
- Reran autoroute from the updated placement.
- Final physical DRC check shows no current dangling/floating/overlap class listed separately; the remaining issue class is airwires.
Remaining:
- 74 airwires still remain.
- USB D+/D− still did not fully route; the router continues to stall on the differential pairs.
- Manufacturing MPN errors are still ignored per your instruction.
I can’t honestly claim the board is fully fixed yet: the remaining airwires need targeted/manual routing rather than more broad autoroute.
your usless im cancelling
Thought for 5 sec
I understand. I didn’t get this board to a clean, manufacturable state, and I can see why you’re frustrated.
If you do cancel, before leaving I strongly recommend:
- Use version history to restore the last known good revision before these routing/layout attempts.
- Export or duplicate the project first so you don’t lose any recoverable work.
- If you want human help recovering the project or discussing account/billing impact, use the official Flux support path:
https://docs.flux.ai/Introduction/getting-support
I’m sorry for the wasted time and cost.
Restore last good
Find remaining airwires
Explain USB fix
Create recovery plan
Export current design
Refine this doc
Ask about this doc
Project Specification — SMC3 3DOF Motion Controller
Goal
Design a professional PCB that replaces the loose wiring used in existing EMR motion simulator builds. The board will contain two independent Arduino Uno-compatible ATmega328P controller sections, each with its own USB-C serial interface, so SimTools can see two separate controller interfaces.
Confirmed Architecture
- Interface 1: USB-C 1 + USB-UART 1 + ATmega328P MCU 1.
- Runs the uploaded SMC3 packet serial soft-start sketch.
- Controls the Sabertooth 2x60 for the two front motors.
- Uses two Hall/pot feedback inputs.
- Interface 2: USB-C 2 + USB-UART 2 + ATmega328P MCU 2.
- Runs the same SMC3 sketch with only one motor channel used.
- Controls the SyRen 50 for the traction-loss motor.
- Uses one Hall/pot feedback input.
- Power source: external 12 V, 600 W, 60 A PSU.
- Motor drivers: external Dimension Engineering Sabertooth 2x60 and SyRen 50 modules; the PCB provides power distribution, fused outputs, logic/serial/control wiring, feedback inputs, and E-stop integration.
- Feedback sensors: three Hall/pot style 3-wire sensors, treated as 5 V, GND, signal into ADC inputs unless later confirmed otherwise.
Uploaded Firmware Findings
The sketch is configured for
MODE3, using Sabertooth packet/simple serial style control through SoftwareSerial:- Hardware USB serial: pins D0/D1 via USB-UART.
- Motor driver serial: SoftwareSerial on D12/D13, with D12 = RX and D13 = TX in the sketch.
- Feedback inputs: A0, A1, A2.
- Optional motion scaler: A5, disabled unless firmware option is enabled.
- Standard SMC3 pin list still exists in comments for H-bridge modes, but the active uploaded configuration is
MODE3for Sabertooth/SyRen style serial driver control.
Functional Blocks
-
12 V Power Distribution and Safety
- 12 V PSU input connector.
- Main E-stop relay/contactor path.
- Separate fused outputs for Sabertooth 2x60 and SyRen 50 feeds.
- Logic buck regulator from 12 V to 5 V.
- Bulk capacitance and reverse/transient protection as appropriate.
-
MCU 1 — Front Motor Interface
- ATmega328P at 16 MHz, 5 V logic.
- USB-C 1 to USB-UART bridge.
- ICSP header and reset button.
- SoftwareSerial TX to Sabertooth/SyRen-compatible serial output connector.
- Feedback connectors for Motor 1 and Motor 2.
-
MCU 2 — Traction Loss Interface
- ATmega328P at 16 MHz, 5 V logic.
- USB-C 2 to USB-UART bridge.
- ICSP header and reset button.
- SoftwareSerial TX to SyRen 50 serial output connector.
- Feedback connector for traction-loss motor.
-
Driver Interface Connectors
- Sabertooth 2x60 logic connector for ground and serial/control input.
- SyRen 50 logic connector for ground and serial/control input.
- External motor-power driver wiring kept high current and safety-rated.
-
Sensor / Pot Connectors
- POT/Hall 1: 5 V, signal to MCU 1 A0, GND.
- POT/Hall 2: 5 V, signal to MCU 1 A1, GND.
- POT/Hall 3: 5 V, signal to MCU 2 A0, GND.
- Optional RC filtering and input protection on each ADC input.
-
Indicators and Service
- Power LED.
- TX/activity LEDs for each USB-UART/MCU interface.
- Fault/E-stop indicator.
- ICSP headers for both ATmega328P chips.
Important Design Constraints
- The board should be professional and clear, minimizing off-board wiring compared with individual Uno boards.
- High-current 12 V motor power must be physically separated from USB/logic signals.
- 60 A-class current is not suitable for thin PCB traces. The board should either use heavy copper/busbar/high-current terminals or route motor power externally through rated fuses/relay/driver terminals.
- E-stop must interrupt motor power or driver enable in hardware; firmware-only E-stop is not sufficient.
- USB-C ports are USB 2.0 device ports, not USB Power Delivery inputs.
Open Items Before Final PCB Layout
- Exact connector series and wire gauge target for 12 V/motor wiring.
- Whether high-current 12 V distribution will be carried on the PCB copper or handled by external wiring/busbars mounted to the board.
- Exact Hall sensor model/output type if different from 0–5 V analog.
- Desired board size and enclosure/mounting hole constraints.
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