Electronics Boards Overview - thepinkmile/Enigma-NG GitHub Wiki

Enigma-NG Board Overview

Status: Reference Project: Enigma-NG Author: Izzyonstage & GitHub Copilot Version: v1.0.0 Last Updated: 2026-04-20

1. Overview

The Enigma-NG system uses a modular, museum-grade architecture built around a fixed Controller motherboard and two removable service modules: the Power Module and the Stator.

The design/Standards/Global_Routing_Spec.md applies to all boards except where a board-level design spec explicitly records an exemption.

2. Power Rail Glossary

  • 3V3_ENIG: Provided by the Power Module TPS75733KTTRG3 LDO. Powers all CPLDs, JTAG interface, I2C logic, rotor stack, and Controller digital I/O.
  • 5V_MAIN: Provided by the Power Module dual-buck stage. Powers the CM5 main supplies and the 5V system bus.
  • GND: Common power and signal ground reference.
  • GND_CHASSIS: Safety earth / EMI reference plane.
  • PWR_GD: Direct PM -> Controller rail-health signal from the MCP121T supervisor.

Only the Power Module implements the intentional GNDGND_CHASSIS bond.

3. Telemetry Sensor Responsibility

  • Power Module INA219 (0x40): monitors 5V_MAIN
  • Stator INA219 (0x45): monitors rotor-stack 3V3_ENIG
  • Power Module PCA9534A (0x3F): virtualises PM status lines and SW1 RGB runtime control

4. I2C Bus Map

  • I2C1 (SCL/SDA) originates on the Controller and fans out in parallel:
    • Controller -> Power Module over J3
    • Controller -> Stator over J5
    • Stator -> Settings Board over J_CFG
    • 0x09: LTC3350 supercap charger / monitor (Power Module)
    • 0x0B: Smart Battery / SMBus monitor (Power Module)
    • 0x20: MCP23017 U_EXP1 (Stator ENC monitoring)
    • 0x21: MCP23017 U_EXP2 (Stator virtual keypress / servo control)
    • 0x22: MCP23017 U_EXP4 (Stator CPLD config output driver)
    • 0x23: MCP23017 U_EXP_SW_IN (Settings Board switch input)
    • 0x24: MCP23017 U_LED_B1 (Settings Board Bank 1 LED controller)
    • 0x25: MCP23017 U_LED_B2 (Settings Board Bank 2 LED controller)
    • 0x28: STUSB4500 USB PD controller (Power Module)
    • 0x3F: PCA9534APWR PM-local GPIO expander (Power Module)
    • 0x40: INA219 (Power Module)
    • 0x45: INA219 (Stator)
    • 0x60: PCA9685 (Stator servo PWM)

5. System Architecture & Status

Board Name Role Stackup Status
Controller Board Fixed motherboard; CM5 host; external RJ45, Ethernet ESD/magnetics, PoE front-end, HDMI, USB 3.0, and service docks for PM + Stator 6-Layer / 2oz In Review
Encoder Module Dual-use Keyboard / Plugboard / Lampboard logic using 2x Intel MAX II EPM240T100I5N CPLD 4-Layer / 2oz In Review
Extension Board Re-buffers TCK/TMS between 5-rotor groups; forwards/reinjects clean power and bridges TTD_RETURN between stacks 4-Layer / 2oz Design Locked
JTAG Daughterboard Internal FT232H-based hardware programmer 4-Layer / 2oz Design Locked
Power Module Removable power-conditioning / UPS cartridge with supercaps, eFuse, OR-ing, USB-C input, battery input, and PM-local status expander 6-Layer / 2oz In Review
Reflector Board Mandatory terminating turnaround board for the rotor stack return path 4-Layer / 2oz Design Locked
Rotor Module Smart encryption units (30x) with MAX II EPM570T100I5N CPLDs 4-Layer / 2oz Architecture Set
Settings Board Panel-mount switch and RGB LED configuration interface on the shared Stator I2C-1 bus 4-Layer / 2oz In Review
Stator Board Removable vertical daughterboard; rotor-stack backplane and CPLD routing hub 4-Layer / 2oz In Review

6. Notes

  • The Controller ↔ Power Module dock uses three TE 10-position 2.5mm connectors.
  • The Controller ↔ Stator dock uses two Molex EXTreme Guardian HD hybrid connectors.
  • Rotor / Extension / Reflector interconnects use Samtec Edge-Rate connectors.
  • All external I/O is grouped on the Controller side of the enclosure.