Phi Mainboard 5LC is a 3D printer controller with a focus on network connectivity. In addition to all the things that other controller boards can do, Phi provides a web interface that you can use to interact with your printer over the local network. With Phi, you no longer need a separate single-board computer (like a Raspberry Pi), which saves you money, simplifies setup, and spares you from long start-up times.

While Phi’s feature set is geared toward 3D printers, it can also be used to drive other digital-fabrication equipment, such as CNC machines.

High-resolution images: left, middle, right

Phi Mainboard 5LC Rev1 (left, green) and Rev2 (right, black)

Rev1 board installed on a Prusa MK3S

Why Phi?

Powerful Brains • Flexible Networking • Fast & Functional Web Interface • Runs RepRapFirmware • Support for a Wide Range of Hardware • Open Source

Powerful Brains

Brains—plural. Powering Phi are two processors: an ESP32-S3-WROOM module and a SAM E51 microcontroller. The former handles networking, SD storage, USB communication, and displays; the latter handles kinematics, stepping, digital and analog I/O, and other realtime controls. This delegation of roles ensures that motion control and other time-sensitive operations do not get bogged down by networking.

Flexible Networking

Whether your network is wired or wireless, Phi has you covered. You might start out using your printer over Wi-Fi, then decide to run cable at some point in the future. Or vice-versa!

Note: Because the Wi-Fi drivers for Espressif chips are available only as binary blobs (without source code), Phi will ship with firmware support for Ethernet only. For personal use, however, you will be able to build and upload firmware with Wi-Fi support. We will strive to make this process easy, even for non-developers, and to ensure that it does not require specialized tools.

Fast & Functional Web Interface

Phi’s web interface, Duet Web Control, allows you to upload G-code files, configure settings, start jobs, control the device, and monitor prints. It even adapts to various screen sizes, so you can use it from a PC, a tablet, or a smartphone.

Spend Less Time Waiting & More Time Printing

Ten seconds after you power it on, Phi will be serving the Duet Web Control interface, which will await your instructions. And G-code uploads are fast, as well: up to 800 KiB/s on Wi-Fi and 600 KiB/s on Ethernet (though of course YMMV).

Wi-Fi

Ethernet

Monitor Your Printer With an IP Camera

Phi might not have a USB port for connecting a webcam, but you can still use some IP cameras to get a video feed of your machine in the web interface. One affordable, DIY option is to use an ESP32-CAM module.

Runs RepRapFirmware

Phi runs RepRapFirmware, which has a huge legacy in the 3D-printing world and is credited with introducing numerous advancements. It supports Cartesian, delta, CoreXY, polar, and most other kinematics. More importantly, you can configure RepRapFirmware without having to rebuild it. Most settings in the firmware, especially those related to kinematics, are configured using G-Code, so you can even make changes on the fly!

Support for a Wide Range of Hardware

Display Options

If you want to go all-out with the display, Phi supports PanelDue in both 4-pin and 10-pin configurations. If you’re interested in a more basic display (since there’s a web interface anyway), Phi also supports ST7920/ST7565-based 128 x 64 graphical LCD displays like the RepRapDiscount Full Graphic Smart Controller and the FYSETC Mini 12864.

Steppers Galore

Phi includes five built-in stepper drivers. If you need more, a Duet 3 Expansion Mini 2+ will bring you up to a total of seven stepper drivers. And if seven still isn’t enough, you can always add CAN-FD expansion boards like the Duet 3 Expansion 3HC, the Duet 3 Toolboard 1LC, and the Duet 3 Expansion 1XD. Or connect several of these boards to the CAN-FD bus, and drive a truly absurd number of steppers, heater outputs, fans, thermistors, etc.

Other Modules You Expect

Phi supports all of the expansion options you might expect - NeoPixels, BLTouch and other Z-probes, thermocouples or PT100s (using daughterboards), SSRs (for heated chambers), VFDs, accelerometers, filament monitors, etc.

Open Source

Phi was created using open source and freely-available tools: KiCAD for schematic capture and PCB layout and GCC and CMake for firmware development. Phi’s schematic, PCB layout, and firmware will be publicly available on our GitHub shortly after the product ships.

Features & Specifications

Board-Layout Diagram

Technical Specifications

Physical

• 123 x 100 mm, M4 mounting holes
• 4 layers with 2 oz. outer copper layers (for better heat dissipation)

Processors

• Espressif ESP32-S3-WROOM-1-N8 ¹
  • 512 KB SRAM
  • 8 MB SPI flash
  • Dual-core 240 MHz Xtensa LX7
• Microchip ATSAME51N19A
  • 192 KB SRAM
  • 512 KB flash
  • 120 MHz Cortex-M4F

Interfaces

• Micro SD
  • SD v3.0 and v3.01, SDIO v3.0, CE-ATA v1.1, MMC v4.41
• Micro USB
  • USB 2.0 full-speed (up to 12 Mbit/s)

Networking & Connectivity

• Bluetooth 5 LE
• 802.11b/g/n 2.4 GHz Wi-Fi
• 10/100 Base-T Ethernet

Power

• Input voltage (VIN) range 11 V - 25 V
• Input connector rated up to 25 A
• On-board regulators
  • 1x 12 V, 3 A
  • 2x 5 V, 3 A
  • 2x 3.3 V, 1 A

Machine Features

• 5x TMC2209 stepper drivers
  • 2 A RMS
  • Up to x256 microstepping
  • StealthChop2 (for silent operation)
  • StallGuard2 (for stall detection and sensorless homing)
• 2x extruder heaters (each up to 5 A)
• 1x bed heater (up to 15 A)
• 3x thermistors or PT1000s
• 4x PWM fans, 1x always-on
  • 2x with tach input
  • Selectable betwen VIN and 12 V in two banks
• 1x VFD/Laser/Servo (5 V output)
• 7x GPIO ports (for endstops, filament monitors, Z-probes, SSRs, etc.)
  • 30 V tolerant input
  • 3.3 V output

Specialty Ports

• EXP1, EXP2
• PanelDue 4-pin & 10-pin
• NeoPixel
• CAN-FD expansion
• Stepper expansion
• Thermocouple or PT100 expansion

Comparisons

Support & Documentation

You will find Phi’s documentation in the hardware design repository wiki. We will add materials, including guides and technical articles, by the time boards ship our to backers. Meanwhile, if you have a question that just can’t wait, or if you want to see a topic covered in our documentation, please feel free to reach out using the Ask a technical question link below.

Manufacturing Plan

Phi Mainboard 5LC will be assembled, tested, and packaged by our contract manufacturer in the Philippines. They will assist in sourcing the PCB and components using their extensive network. We chose this particular company, which caters to both local and international clients, because of their extensive experience with electronics manufacturing. Furthermore, having an onshore manufacturer will give us faster lines of communication, allow us to monitor the entire process more closely, and facilitate tighter coordination should an issue arise.

Fulfillment & Logistics

After testing and packaging the production batch of Phi boards, our CM will send them to Crowd Supply’s fulfillment partner, Mouser Electronics, who will distribute orders to backers worldwide. You can learn more about Crowd Supply’s fulfillment service under Ordering, Paying, and Shipping in their guide.

Risks & Challenges

The pandemic-induced global component shortage continues to be the greatest risk for any electronics project – and it’s no different for Phi. We tried to mitigate this risk by using well stocked components wherever possible. This is not a full solution, however, as integrated circuits (ICs) remain in short supply. Fortunately, reputable vendors appear to have begun restocking the ICs we need for Phi, and we expect to have stock available in the coming months. Once we hit our funding goal, we will prioritize the procurement of these components in particular.

¹ The final hardware will likely have an ESP32-S3-WROOM-1U-N8 instead of an ESP32-S3-WROOM-1-N8. These modules are identical, except for the fact that the ESP32-S3-WROOM-1U-N8 uses an external antenna. ESP32-S3-WROOM-1U-N8 is not in mass production yet, but it is mentioned in Espressif’s datasheet. If this is the module that does end up in the final hardware, then an external antenna will be included in the box. Backers will be kept informed regarding this topic through updates.

² Includes free shipping within the US.

³ Filastruder price as of October 2021 + $9 to cover estimated US shipping charges. Filastruder is a genuine reseller for Duet3D.

⁴ Robosprout price as of October 2021 + $9 to cover estimated US shipping charges. Robosprout is an authorized reseller for Smoothieware.

⁵ BigTreeTech price as of October 2021 for the board only + $9 to cover estimated US shipping charges. Adding 5x TMC2209 StepSticks ($22) + Raspberry Pi 4 ($45) + Micro SD ($7) + power supply ($10) would bring the total price to $136.