DeskPi Super4C (DP-0040)

SKUDP-0040

Form FactorStandard Mini-ITX (170 × 170 mm)

Compute Nodes4× Raspberry Pi CM5

Storage Support4× M.2 2280 NVMe PCIe Slots

🛒 Buy DeskPi Super4C on Official Store →

📊 Overview 🔌 Power & Hardware 🌐 ESP32 Controller 💾 Flash eMMC 💻 Ansible Cluster Guide

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Overview

Introduction

Super4C is a cluster-based hardware built on the Raspberry Pi CM5, supporting four channels of CM5 and extending almost all CM5 interfaces for powerful device connectivity. It also integrates an ESP32 module for remote management of the entire cluster. (Referred to as "the motherboard" throughout this document.)

Key Features

Power:

• External DC 12V–20V barrel connector (ID 2mm, OD 6.6mm); redundant dual-socket input (DC1/DC2); auto-selects higher voltage; reverse polarity protection + fuse circuits
• Four-channel independent DC/DC → 5V; independent per-channel PWR_OFF button; ~0.5s hardware power-on delay to prevent inrush current

Per CM5 channel (×4):

• 1× micro HDMI 2.0 interface
• 1× USB 3.0 (Port 0, max 0.9A output)
• 1× USB 2.0 Type-C (D+/D- only, no VBUS)
• 1× 1Gbps Ethernet (native RJ45)
• 1× 2.5Gbps Ethernet (via USB 3.0 Port 1 expansion)
• 1× microSD card (CM5 Lite only)
• 1× M.2 M-key PCIe 2280 slot
• 1× 4-pin JST-SH PWM fan
• 1× RTC battery interface
• 2× MIPI DSI/CSI-2 (22-pin 0.5-pitch FPC)
• Jumper header for eMMC/EEPROM disable; GPIO8–11 expansion

Management (ESP32):

• ESP32-WROOM-32E-N4 with 2.4GHz Wi-Fi + Bluetooth
• W5500 100Mbps wired network expansion
• UART download interface (J47); I2C expansion (J12/J16)
• Two INA3221 chips monitoring 6 voltage/current channels

Tested NVMe SSD Compatibility List

The M.2 2280 M-Key slots interface directly with the CM5 PCIe lane. The following high-performance SSD models have been verified:

#	SSD Model	Interface	Capacity	Verification Status
1	Western Digital Black SN7100	PCIe Gen 4.0 NVMe	1 TB	✓ Verified
2	Western Digital Black SN8100	PCIe Gen 5.0 NVMe	1 TB	✓ Verified
3	Western Digital Black SN770	PCIe Gen 4.0 NVMe	2 TB	✓ Verified
4	Fanxiang Jing Series	PCIe Gen 4.0 NVMe	512 GB	✓ Verified
5	Lexar NQ790	PCIe Gen 4.0×4 NVMe	2 TB	✓ Verified
6	Samsung 990 PRO	PCIe Gen 4.0 NVMe	2 TB	✓ Verified

Note: Due to the CM5 single PCIe Gen 2.0/3.0 x1 lane limitation, theoretical sequential read/write rates are capped accordingly.

Diagram Block

Hardware

Power Input

The main power input uses a barrel connector (ID 2mm, OD 6.6mm), DC 12V–20V. Two sockets (DC1/DC2) support redundant input; when two voltages differ, the board automatically uses the higher one.

Power Protection

Main power passes through protection, sampling, reverse polarity, and fuse circuits before powering internal components and the J15 fan output.

When connecting a fan, ensure its rated voltage matches the main power supply voltage.

5V DC/DC and Reset Buttons

Four independent DC/DC channels supply 5V per CM5. Each channel has a PWR_OFF button (SW3/4/5/6) that independently resets that channel's power.

Voltage & Current Monitoring

Two INA3221 chips (I2C 0x40 and 0x41) monitor 6 channels:

• INA3221 #1 (0x40): DC1 input; DC2 input; 5V channel 1
• INA3221 #2 (0x41): 5V channel 2; 5V channel 3; 5V channel 4

Interfaces

USB 3.0

Connected to CM5 USB3.0 Port 0. Max 0.9A to external devices.

USB 2.0 (Type-C)

D+/D- only, no VBUS. Used with nRPIBOOT for CM5 programming.

Ethernet (1Gbps)

Native RJ45 from CM5 Gigabit interface. PoE not supported.

Ethernet (2.5Gbps)

Extended from CM5 USB3.0 Port 1. Supports 10/100/1000/2500Mbps.

Fan Interface

Same dimensions and signal definitions as the official CM5 IO board. Compatible with Active Cooler JST cable (mounting holes differ).

RTC Battery

Same interface as official CM5 IO board.

MIPI Interface

22-pin 0.5-pitch FPC, same as official CM5 IO board.

Jumper Headers

IO voltage defaults to +3.3V. Brings out GPIO8–GPIO11 for expansion. PMIC_ENABLE can be controlled via jumpers or ESP32.

ESP32 Pin Allocation

Pin	ESP32	Net Name	Function
2	3V3	3V3	3.3V Power
3	EN	EN	HIGH=ON; wired to SW2
8	IO32	XTAL_32K_P	32.768kHz crystal in
9	IO33	XTAL_32K_N	32.768kHz crystal out
10	IO25	CM5_4_PMIC_ENABLE	Channel 4 Enable
11	IO26	CM5_3_PMIC_ENABLE	Channel 3 Enable
12	IO27	CM5_2_PMIC_ENABLE	Channel 2 Enable
13	IO14	CM5_1_PMIC_ENABLE	Channel 1 Enable
16	IO13	BMC_I2C_SDA	I2C SDA (INA3221 + J12/J6)
23	IO15	BMC_I2C_SCL	I2C SCL (INA3221 + J12/J6)
24	IO2	BMC_PSU1	PSU-1 ENABLE (HIGH=OFF, LOW=ON)
25	IO0	BOOT	Boot strap pin
26	IO4	BMC_PSU2	PSU-2 ENABLE
27	IO16	BMC_PSU3	PSU-3 ENABLE
28	IO17	BMC_PSU4	PSU-4 ENABLE
29	IO5	#SCS_W5500	W5500 SPI-CS
30	IO18	SCLK_W5500	W5500 SPI-CLK
31	IO19	MISO_W5500	W5500 MISO
33	IO21	#INT_W5500	W5500 INT
34	RXD0	BMC_RXD0	UART0 RX (J47)
35	TXD0	BMC_TXD0	UART0 TX (J47)
36	IO22	#RST_W5500	W5500 RST
37	IO23	MOSI_W5500	W5500 MOSI

Buttons

BOOT (SW1): Hold while powering on to enter ESP32 programming mode (via UART J47). In default firmware, holding for >1s then releasing sequentially disables CM5 PMIC_ENABLE signals and 5V DC/DC channels (~0.5s intervals).

EN (SW2): Resets all CM5_PMIC_ENABLE and DC/DC ENABLE signals.

I2C Addresses

Item	Address / Pins	Description
J12	4-pin 2.54mm (GND, 3V3, SDA, SCL)	OLED module header
J16	4-pin 2.54mm (GND, 3V3, SDA, SCL)	Additional I2C devices
INA3221 #1	0x40	DC1, DC2, 5V Ch.1
INA3221 #2	0x41	5V Ch.2, 5V Ch.3, 5V Ch.4

ESP32 & Web Controller

ESP32 Default Firmware

The onboard ESP32 firmware supports:

• Display WiFi mode and IP address on OLED (SSD1306)
• Control power for 4 DC/DC channels and CM5 PMIC_ENABLE signals
• Drive SSD1306 OLED modules
• Sample current on 6 channels (2 DC inputs + 4 × 5V rails)
• Detect W5500 Ethernet connectivity (displays "W55" or "OFF")

The full firmware including web controller is available separately. Source code and schematics will be open-sourced after final firmware testing.

Web Controller

Flash the web-controller firmware to enable remote monitoring and power control via a browser.

Connection Modes

AP Mode (default):

Before connecting to a WiFi network, the board broadcasts:

• SSID: Super4C
• Password: 12345678

Connect to Super4C WiFi, then open 192.168.4.1 in a browser.

Station Mode:

1. Click WiFi Setup in the web interface.
2. Enter your SSID and password.
3. Click Save & Reboot (takes ~10 seconds).
4. After reboot, the OLED shows the new IP address.

Reset to AP Mode:

Hold the BOOT button for more than 5 seconds.

Main Page

Displays:

• Current mode and IP address
• Signal strength and server uptime
• Real-time current for all 6 monitoring channels
• 8 independent power switches: PSU #1–4 and CM5 #1–4

WiFi Configuration

Connect to the Super4C AP, then navigate to 192.168.4.1:

Power Switch Operations

• PSU #1–4: Controls 5V DC/DC per channel — cuts power to CM5, NVMe, SD, USB, 2.5G network in that channel.
• CM5 #1–4: Controls only the CM5 PMIC_ENABLE signal — NVMe, SD, USB, 2.5G remain powered.
• Switch All OFF / ON / Toggle All: Bulk operations — use with caution.

DC1/DC2 are external input channels and cannot be switched. Do not confuse with PSU #1–4.

OLED Display

After attaching an SSD1306 OLED:

Displays WiFi mode/IP and current readings for all 6 channels (in Amps).

Flash & Boot

Flash Image to CM5

Set Up the Board

1. Connect the CM5 to the Super4C board (flat when seated).
2. Fit nRPI_BOOT jumper to GND pin (J2 — disables eMMC boot).

3. Connect USB-C cable from slave port J11 to your host.

Linux

sudo apt install rpiboot
# Connect IO board to power, then:
sudo rpiboot

After a few seconds, the CM5 eMMC appears as /dev/sda or /dev/sdb.

macOS

Build rpiboot from source, then:

rpiboot -d mass-storage-gadget64

Click Ignore when macOS says the disk is unreadable. The CM5 now appears as a mass storage device.

Windows 11

1. Download rpiboot Windows Installer
2. Run installer (do not close any driver windows).
3. Reboot.
4. Connect IO board to power.
5. Launch Raspberry Pi - Mass Storage Gadget - 64-bit from Start menu.

Flash the eMMC

Use Raspberry Pi Imager (recommended), or:

sudo dd if=raw_os_image.img of=/dev/sdX bs=4MiB

After writing, disconnect and reconnect — two partitions appear:

/dev/sdX    <- Device
/dev/sdX1   <- First partition (FAT)
/dev/sdX2   <- Second partition (Linux filesystem)

Example — dumping OS from a Raspberry Pi's MicroSD to CM5 eMMC:

Boot from eMMC

1. Disconnect the nRPI_BOOT jumper from GND.
2. Disconnect the USB slave cable.
3. Power-cycle the board — CM5 boots from the new image.

More Information

Raspberry Pi Official Documentation — Compute Module

Cluster (Ansible)

End-to-End: 4-Node CM5 Cluster with Ansible

0. Hardware & Network Topology

Node	Role	IP Address
Raspberry Pi 5	Ansible Control Node	192.168.10.1/24
CM5-01	Compute Module 5	192.168.10.11
CM5-02	Compute Module 5	192.168.10.12
CM5-03	Compute Module 5	192.168.10.13
CM5-04	Compute Module 5	192.168.10.14

1. Prepare the Control Node

sudo apt update && sudo apt full-upgrade -y
sudo apt install -y python3-pip sshpass jq
pip3 install --user ansible-core==2.16
echo 'export PATH=$PATH:~/.local/bin' >> ~/.bashrc && source ~/.bashrc

mkdir -p ~/cm5-cluster/{inventory,group_vars,playbooks,roles,report}
cd ~/cm5-cluster

2. Inventory & SSH Setup

Create inventory/hosts.yml:

all:
  children:
    cm5_cluster:
      hosts:
        CM501: {ansible_host: 192.168.10.11}
        CM502: {ansible_host: 192.168.10.12}
        CM503: {ansible_host: 192.168.10.13}
        CM504: {ansible_host: 192.168.10.14}
      vars:
        ansible_user: pi
        ansible_ssh_pass: raspberry
        ansible_ssh_common_args: '-o StrictHostKeyChecking=no'

Create playbooks/init-ssh.yml:

---
- hosts: cm5_cluster
  gather_facts: no
  tasks:
    - name: Push public key
      authorized_key:
        user: pi
        key: "{{ lookup('file', '~/.ssh/id_ed25519.pub') }}"

Run once:

ssh-keygen -t ed25519 -f ~/.ssh/id_ed25519 -N ''
ansible-playbook -i inventory/hosts.yml playbooks/init-ssh.yml

3. Basic System Initialization

playbooks/site.yml:

---
- name: Initialize all CM5 nodes
  hosts: cm5_cluster
  become: yes
  roles:
    - common

roles/common/tasks/main.yml:

---
- name: Expand root filesystem
  shell: raspi-config --expand-rootfs
  notify: reboot

- name: Set unique hostname
  hostname:
    name: "{{ inventory_hostname }}"

- name: Update system
  apt:
    update_cache: yes
    upgrade: dist

- name: Install common packages
  apt:
    name: [python3-venv, python3-dev, build-essential, git, htop, vim]
    state: present

handlers:
  - name: reboot
    reboot:

ansible-playbook -i inventory/hosts.yml playbooks/site.yml

4. Python Venv & Data-Science Packages

playbooks/venv.yml:

---
- name: Deploy Python venv with AI/ML packages
  hosts: cm5_cluster
  become: yes
  vars:
    venv_path: "/home/{{ ansible_user }}/venv"
    python_packages: [pandas, numpy, opencv-python, matplotlib, seaborn, xgboost, pillow, onnxruntime]
  tasks:
    - name: Create virtualenv
      command: python3 -m venv {{ venv_path }}
      args:
        creates: "{{ venv_path }}/bin/activate"
    - name: Upgrade pip
      pip:
        executable: "{{ venv_path }}/bin/pip"
        name: pip
        state: latest
    - name: Install packages
      pip:
        executable: "{{ venv_path }}/bin/pip"
        name: "{{ python_packages }}"
    - name: Auto-activate venv on login
      copy:
        dest: /etc/profile.d/venv.sh
        mode: '0644'
        content: |
          [ -d "{{ venv_path }}" ] && source {{ venv_path }}/bin/activate

ansible-playbook -i inventory/hosts.yml playbooks/venv.yml

5. Useful Playbooks

Batch shutdown / reboot:

ansible-playbook -i inventory/hosts.yml playbooks/shutdown.yml
ansible-playbook -i inventory/hosts.yml playbooks/reboot.yml

Get CPU temperature:

# playbooks/cpu_temp.yml
- name: Retrieve CPU temperature from all CM5 nodes
  hosts: cm5_cluster
  gather_facts: no
  become: no
  tasks:
    - name: Execute vcgencmd measure_temp
      ansible.builtin.command: vcgencmd measure_temp
      register: temp_raw
    - name: Parse temperature
      ansible.builtin.set_fact:
        cpu_temp: "{{ (temp_raw.stdout | regex_replace('temp=', '') | regex_replace(\"'C\\n\", '')) }}"
    - name: Display temperature
      ansible.builtin.debug:
        msg: "Host {{ inventory_hostname }} CPU: {{ cpu_temp }}°C"
    - name: Append to summary file
      ansible.builtin.lineinfile:
        path: "./cpu_temp_summary.txt"
        line: "{{ '%Y-%m-%d %H:%M:%S' | strftime }} - {{ inventory_hostname }} - {{ cpu_temp }}°C"
        create: yes
      delegate_to: localhost

Quick Reference

Action	Command
Check connectivity	ansible cm5_cluster -i inventory/hosts.yml -m ping
Ad-hoc shell	ansible cm5_cluster -a "uname -a"
View JSON report	cat ~/cm5-cluster/report/*.json | jq -s .

Enjoy your fully-automated CM5 cluster!