Hardware Setup

This guide covers the hardware connections and requirements for the TMC9660 motor controller.

Pin Connections

SPI Communication Interface 

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MCU                    TMC9660
──────────────────     ───────────────────────────────
MOSI (GPIO7)      ───────> SPI MOSI
MISO (GPIO2)      <─────── SPI MISO
SCLK (GPIO6)      ───────> SPI SCLK
CS   (GPIO18)     ───────> SPI CS

Control Pins 

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MCU                    TMC9660
──────────────────     ───────────────────────────────
RST  (GPIO22)     ───────> RST     (Reset, active HIGH)
DRV_EN (GPIO20)   ───────> DRV_EN  (Driver Enable, active HIGH)
FAULTN (GPIO19)   <─────── FAULTN  (Fault Output, active LOW, open-drain)
WAKE (GPIO21)     ───────> WAKE    (Wake Input, active LOW)

UART Communication Interface (Alternative) 

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MCU                    TMC9660
──────────────────     ───────────────────────────────
TX   (GPIO5)      ───────> UART RX (GPIO6 on TMC9660)
RX   (GPIO4)      <─────── UART TX (GPIO7 on TMC9660)

Power and Ground 

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MCU                    TMC9660
──────────────────     ───────────────────────────────
GND              ───────> GND (Common ground)
3.3V / 5V        ───────> VCC (if needed for level shifting)

Pin Functions

Control Pins (Output from Host)

  • RST (Pin 22): External System Reset Input
    • Device remains in reset while this pin is in its active state
    • Has internal pull-down resistor
    • Active level depends on board implementation
  • DRV_EN (Pin 21): Driver Enable Input
    • Enables the motor driver outputs
    • Has internal pull-down resistor
    • Active level depends on board implementation
  • WAKE (Pin 19): Wake Input
    • Drive to active state to enable power-up and exit from hibernation mode
    • When not shorted to VSA, external pull-down resistor recommended
    • Active level depends on board implementation

Status Pins (Input to Host)

  • FAULTN (Pin 20): FAULT Output Signal (open drain)
    • Indicates busy state during bootstrapping or severe error
    • Active level depends on board implementation
    • Use gpioRead(TMC9660CtrlPin::FAULTN, signal) to check fault status

Electrical Specifications

SPI Interface

  • Speed: Up to 4 MHz
  • Data Size: 8 bytes per transaction
  • Mode: SPI Mode 0 or 3 (CPOL=0, CPHA=0 or CPOL=1, CPHA=1)
  • CS Polarity: Active LOW

UART Interface

  • Baud Rate: 9600 to 1000000 baud, or autobaud
  • Data Format: 8 data bits, 1 stop bit, no parity
  • Frame Size: 9 bytes per transaction

Power Requirements

  • Motor Supply (VM): 12V to 48V (depends on motor)
  • Logic Supply (VCC): 3.3V or 5V
  • Common Ground: Must be connected between MCU and TMC9660

Motor Connections

BLDC Motor (3-Phase)

  • U, V, W: Three-phase motor connections
  • Hall Sensors: Connect to Hall connector (GPIO2, 3, 4)
  • ABN Encoder: Connect to Encoder connector (GPIO8, 13, 14)

Stepper Motor

  • Step/Direction: External step/direction interface
  • Reference Switches: Left (GPIO2), Right (GPIO3), Home (GPIO4)
  • ABN Encoder: Connect to Encoder connector (GPIO8, 13, 14)

Typical Application Circuit 

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┌─────────────────────┐         ┌─────────────────────┐
│  MCU (ESP32/STM32) │         │   TMC9660 Board    │
│                     │         │                     │
│  SPI Interface:     │         │                     │
│  • MOSI      ──────┼─────────┼─> SPI MOSI          │
│  • MISO      <──────┼─────────┼─< SPI MISO          │
│  • SCLK      ───────┼─────────┼─> SPI SCLK          │
│  • CS        ───────┼─────────┼─> SPI CS            │
│                     │         │                     │
│  Control Pins:      │         │                     │
│  • RST       ───────┼─────────┼─> RST               │
│  • DRV_EN    ───────┼─────────┼─> DRV_EN            │
│  • FAULTN    <───────┼─────────┼─< FAULTN            │
│  • WAKE      ───────┼─────────┼─> WAKE              │
│                     │         │                     │
│  GND         ───────┼─────────┼─> GND               │
│                     │         │                     │
│                     │         │  Motor:             │
│                     │         │  • U, V, W (BLDC)   │
│                     │         │  • Step/Dir (Stepper)│
└─────────────────────┘         └─────────────────────┘

Setup Steps

  1. Power Off: Ensure both MCU and TMC9660 are powered off
  2. Connect SPI Interface: Wire MOSI, MISO, SCLK, CS
  3. Connect Control Pins: Wire RST, DRV_EN, FAULTN, WAKE
  4. Connect Ground: Common ground connection
  5. Connect Motor: Wire motor and sensors (if applicable)
  6. Power On: Power MCU first, then TMC9660

Next Steps