The PCB Placement Pass was already reconciled against the live board; no additional project changes were made this session.
Verified state:
All 134 footprints are placed: 81 top / 53 bottom
J3 USB-C: (27, −32.9) mm, bottom edge
J4 USB-A: (44.72, −21) mm, right edge
J5 USB-B: (−44.5, −21) mm, left edge
BT1: provisional bottom-side placement at (0, 2) mm
J1/J2 remain locked at (±17, 12.5) mm, 90° rotation, preserving the official 34 mm CM5 spacing
Board remains 110 × 75 mm, four copper layers
No reported component-body overlaps or out-of-bounds footprints
No routed traces exist; 285 airwires remain
The 18 pre-existing legacy GND via nodes remain
Remaining issues:
BT1’s 94.6 × 26 mm body conflicts with the fixed CM5/antenna region. Its position cannot be accepted until enclosure and vertical-clearance geometry are resolved.
D3 retains a library/differential-pair warning that must be reviewed before USB routing.
Routing congestion is expected near J1, U5, R17, R18, and TP11.
Connector plug/enclosure clearance has been planned geometrically but still requires enclosure-level validation.
Execution stopped because your ACUs ran out.
Received notification from "PCB Placement Pass" that it finished — picking the work back up.
The PCB Placement Pass was already fully reconciled against the live board. This is a duplicate completion notification, so no further changes were made.
Placement is complete; remaining unresolved items are the provisional BT1/CM5 mechanical conflict, the D3 USB warning, and enclosure-level connector clearance validation. No routing or schematic changes were performed.
This is a duplicate completion notification. The placement pass was already reconciled, and the user subsequently ordered all work stopped. No further inspection, placement, routing, or project changes were performed.
Small unattended Linux/.NET appliance installed aboard commercial vessels.
Receives existing NMEA/AIS via USB, processes and stores data locally, sends a serial stream to a Rose Point laptop, and uploads over Wi-Fi when available.
Prototype is not navigation-critical and does not claim IEC 60945 compliance, but should follow robust embedded/industrial practices.
What the Device Should Do
Operate from ordinary 5 V USB-C chargers or computer ports without assuming 3 A capability.
Continue through short input-power interruptions from one protected, replaceable 21700 Li-ion cell.
Allow Linux to perform orderly low-battery shutdown and automatically restart when external power returns.
Provide one service USB connection for eMMC recovery, debug, and future gadget modes.
Expose only the required product interfaces and indicators.
Main Features
CM5 with two Hirose DF40C-100DS-0.4V(51) connectors and four M2.5 module mounts.
DATA IN: right-angle USB-A female host port, USB 2.0 data, protected/current-limited VBUS near 500 mA.
ROSEPOINT: right-angle full-size USB-B female through FT231XS-R; outgoing CM5 UART presented as USB serial with no system-power backfeed.
SERVICE / POWER: one USB-C receptacle, 5 V sink/UFP, CM5 USB 2.0 OTG/device connection, nRPI_BOOT recovery provision.
Type-C source-current detection, protected USB input, standalone charger/power path, 21700 battery protection, 5.1 V boost, MAX17048 gauge, RTC backup, power-return wake logic, one button, one intentionally dim RGB LED.
System Architecture
Diagram
Hardware Subsystems
Compute
CM5102032 removable module; no microSD, HDMI, MIPI, PCIe/M.2, Ethernet, 40-pin header, audio, or display connectors.
USB and Serial
USB-A host input with ESD and protected 500 mA-class VBUS switch.
USB-C service/device interface with USB 2.0 differential routing and recovery boot access.
FT231XS-R USB device bridge driven primarily by CM5 UART TX; Rose Point VBUS used only for device detection/supply requirements and isolated from the system 5 V rail.
Power and Battery
TUSB320LAI current advertisement detection drives hardware input-current selection.
TPS259470 eFuse immediately after USB-C VBUS.
BQ25616 standalone 1-cell charger/power path, nominal charge current about 1.5 A subject to analysis.
One Molicel INR21700-P45B in PCB holder, with reverse insertion protection and independent BQ2970-family protection plus back-to-back MOSFETs.
TPS61088 synchronous boost to 5.1 V, minimum 3 A continuous design target with transient margin.
MAX17048 gauge on I2C with ALERT to GPIO.
Control, RTC, and Status
CM5 PWR_BUT button and gated external-power-return wake pulse only while CM5 is off.
CM5 RTC backed from protected battery through an ultra-low-IQ regulator compatible with VBAT limits.
One common-anode RGB LED, dimmed for a dark wheelhouse; use CM5 LED_nPWR/LED_nACT where useful and buffer as required.
Interfaces and Connections
External connectors are limited to DATA IN USB-A, ROSEPOINT USB-B, and SERVICE / POWER USB-C.
Internal/test provisions include nRPI_BOOT, PWR_BUT, PMIC_EN, power-present, gauge ALERT, UART and FTDI signals, and specified power rails.
Optional CM5 U.FL to enclosure SMA pigtail; no second RF switch.
Power and Runtime Expectations
Source: ordinary 5 V USB-C; no USB-PD high-voltage modes.
Battery: standard 4.2 V-charge 21700 Li-ion, validated with P45B 4.5 Ah cell.
Runtime objective: approximately 1–2+ hours under normal Edge13 workload.
Battery may supplement a weak source; input must not exceed advertised Type-C current.
Linux initiates orderly shutdown around 10–15% SOC; hardware protection is the final deep-discharge safeguard.
Power Tree and Power Budget
Detailed worst-case rail/load/current, charger, boost, thermal, and runtime calculations will be maintained in the pre-layout design review.
All power-path ratings must be derived from worst-case minimum battery voltage, CM5/peripheral peaks, conversion efficiency, cable drop, thermal limits, and MLCC derating.
Manufacturing and Assembly Expectations
Low-volume professional PCBA, initially JLCPCB/LCSC-oriented.
At least four layers, 1 oz copper minimum unless analysis justifies more.
Prefer stocked, reputable, long-lived parts and verified manufacturer footprints.
Post-PCBA work limited to CM5, cell, optional antenna pigtail, enclosure, and thermal hardware.
Silkscreen: connector labels, polarity, and EDGE13 MAINBOARD REV A.
Firmware-Relevant Hardware Requirements
Raspberry Pi OS / Linux and Edge13 .NET application.
Linux reads fuel gauge, controls shutdown policy, and may configure USB gadget and antenna selection.
No custom microcontroller firmware; no MCU may be added solely for power management or restart behavior.
Physical Design Expectations
Target PCB no larger than about 85–90 mm × 65–70 mm unless mechanically justified.
DATA IN and ROSEPOINT preferably on opposite ends; USB-C, power button, and RGB LED in one service area.
Four enclosure mounting holes plus four accessible CM5 mounting points.
Board-edge external connectors, vibration-resistant battery retention, passive CM5 cooling clearance, and full CM5 antenna keepout.
No PCB placement or routing until schematic and pre-layout package are approved.
Important Design Decisions
True charger power path plus downstream boost, rather than direct 5 V battery conversion without supplement mode.
Hardware Type-C current-capability response at startup.
Independent analog battery protection and software-managed orderly shutdown.
Power-return wake pulse gated by CM5 power-state indication.
Existing CM5 RTC and antenna resources are reused; no redundant RTC or RF switch.
Required Pre-Layout Deliverables
Complete hierarchical schematic and exact CM5 pin allocation.
USB topology, power tree, battery/UPS state diagram.
Mechanical outline/connector plan and antenna keepout plan.
ERC results and explanation for every intentionally unused CM5 pin.
Explicit assumptions and any identified contradictions or safety concerns.
Assumptions
Final detailed GPIO choices may be selected from CM5 pins that do not conflict with required USB, UART, I2C, LED, boot, and power-control functions.
Exact charge rate, boost component values, battery-protection threshold variant, RTC regulator, logic devices, MOSFETs, TVS arrays, and critical passives remain subject to datasheet, sourcing, thermal, and ERC review.
Enclosure material is initially plastic, with optional external antenna provision retained for a future metal enclosure.
Change Notes
Rev A begins as a clean-sheet CM5 mainboard and explicitly does not reuse the prior Edge13 Interface Board schematic or unverified TPS259470 footprint.