DeskPi Mini Cube (DP-0019)

SKUDP-0019

Target BoardRaspberry Pi CM4 (Compute Module 4)

Storage SupportM.2 NVMe SSD (M-Key 2242)

CoolingAluminum Radiator with PWM Fan

🛒 Buy DeskPi Mini Cube on Official Store →

Description

DeskPi Mini Cube for Raspberry Pi CM4 is a case with a miniature appearance and extremely portable features.

Note: Only supports Raspberry Pi CM4 module

The device provides a mini aluminum alloy radiator and integrates a silent fan that supports PWM speed regulation.

The bottom board provides a wealth of interfaces, supporting dual full-size HDMI interfaces, RJ45 Ethernet interfaces, 2x OTG USB port, and one PCIe interface supports M.2 NVME SSD M-KEY 2242 external storage.

The DIP switch on the back provides the special pins needed to configure the Raspberry Pi CM4 module. (On Compute Module 4 EMMC-DISABLE / nRPIBOOT (GPIO 40) must be fitted to switch the ROM to usbboot mode.)

Otherwise, the SPI EEPROM bootloader image will be loaded instead.

The 40Pin GPIO lead out and reserved RTC clock battery interface.

Features

• Integrated design
• Aluminum alloy radiator with PWM adjustable speed fan
• Power button
• 2 x Full-size HDMI ports
• 2 x OTG USB2.0 port
• 1 x PCIe M.2 NVME M-KEY 2242 SSD slot
• 1 x 40 Pin GPIO lead out
• 1 x DIP switch for mode change (CM4 function change)
• 1 x Onboard PCF85063 I2C RTC module
• 5V USB-C Port Power IN

Gallery

Product Outlook

Rear Ports & Power

Port Definitions

Internal CM4 Carrier Board

Dimensions

IPEX Antenna Specifications

• Center Frequency: 2400–2500 MHz & 4900–5900 MHz
• Connector: IPEX1
• Antenna Cable: 1.13 Coaxial cable with plastic jacket
• Impedance: 50 Ohm
• Gain: ~3 dBi

IPEX1 internal antenna structure

Install IPEX Antenna

Adhere the antenna as shown in the diagram. Remove the protective backing tape and paste the flexible antenna flat against the inside wall of the enclosure:

IPEX antenna placement inside enclosure

RTC Battery Information

Battery Compatibility

The RTC backup battery is not included in the standard package and requires separate purchase.

• Recommended Model: CR1220 3V coin cell with ZH1.25 2-pin connector.

Package Includes

• 1 x DeskPi Mini Cube Enclosure Kit (for Raspberry Pi Compute Module 4)
• 1 x Heatsink and PWM Fan Module
• 1 x IPEX Antenna
• 1 x Mounting Screws and Standoffs Pack

DeskPi Mini Cube package contents

How to Assemble

CM4 Module Installation

1. Step 1: Loosen the four screws on top of the Mini Cube.
2. Step 2: Remove copper pillars and apply the thermal pad onto the Raspberry Pi CM4 module.

   Note: Peel off the protective film on both sides of the thermal pad. Align the CM4 high-density connectors carefully with the carrier board before pressing firmly.

3. Step 3: Fix the aluminum heatsink onto the CM4 module with the copper standoffs.

CM4 installation and heatsink alignment

[Optional] Install M.2 NVMe SSD (M-Key 2242)

1. Remove the screws on the bottom plate of the Mini Cube and remove the SSD carrier daughter board.
2. Insert the M.2 NVMe SSD into the socket at a 30-degree angle and secure it with the mounting screw.
3. Align the daughter board with the header pins on the mainboard and reconnect securely.
4. Replace the bottom cover plate and tighten all screws.

Bottom carrier board and DIP switch configuration

Functionality of power button:

• Short Press: Power on
• Long Press: Power off (Cutoff power)

Please NOTE that if you have not shutdown the system, do not use long press to halt system, it will damage your system, it may cause kernel panic or lost file which are not saved yet.

• Correct Operation: Shutdown system in terminal or desktop, and then long press the button to cut off power.

DIP Switch Functionality

DIP Switch Pinout

The rear DIP switch configures CM4 hardware modes:

• Pin 1: USB OTG Pull Up
• Pin 2: Reserved (Unattended)
• Pin 3: EEPROM_nWP (EEPROM write protection)
• Pin 4: nRPIBOOT (eMMC flashing mode switch)

DIP switch pin distribution and configuration

If you are using Raspberry Pi CM4 with EMMC onboard. please refer to this URL: How to flash the Compute Module in section “Flashing the Compute Module eMMC”

Hardware write-protection must be enabled via software and then locked by pulling the EEPROM_nWP pin low.

How to enable USB2.0 ports besides the USB-C port?

Assume that you are using Raspberry Pi OS (64bit/32bit).

• The latest official image which you can download from: www.raspberrypi.com/software will automatically adding otg_mode=1 in /boot/firmware/config.txt file, so you don't need to modify any parameter in /boot/firmware/config.txt file.

How to Update EEPROM Firmware on Raspberry Pi Compute Module 4 (CM4)

Overview

Unlike earlier Compute Modules, the CM4 uses an EEPROM bootloader stored in on-board storage rather than the boot partition. This means it requires different update procedures compared to standard Raspberry Pi boards.

---

Prerequisites

Item	Description
Host PC	Linux, macOS, or Windows PC with USB port
CM4 + IO Board	CM4 mounted on an official CM4 IO Board or compatible carrier
USB Cable	USB-C or micro-USB cable to connect IO Board to host
usbboot tools	Raspberry Pi usbboot utility installed on the host

Install usbboot (Host PC)

# Clone the official usbboot repository
git clone --depth=1 https://github.com/raspberrypi/usbboot
cd usbboot

# Build (Linux/macOS)
make

# Install dependencies if needed (Debian/Ubuntu)
sudo apt install libusb-1.0-0-dev

---

Method 1: Flash Bootloader EEPROM via USB (Recommended)

This method directly writes the bootloader EEPROM using rpiboot in recovery mode. It is the most reliable method for CM4.

Step 1: Hardware Setup

1. Mount the CM4 onto the IO Board.
2. Ensure the EEPROM_nWP pin is NOT pulled low (write-protection must be disabled).
3. Connect the IO Board's USB slave port to your host PC.
4. Do NOT insert an SD card or eMMC storage if you want to target the EEPROM directly.
5. Power on the IO Board.

Step 2: Flash the EEPROM

Run the recovery command from the usbboot directory:

cd usbboot
sudo ./rpiboot -d recovery

This writes recovery/pieeprom.bin to the CM4's bootloader EEPROM.

Step 3: Re-enable Write Protection (Optional)

Once flashing completes successfully, you may pull EEPROM_nWP low again to prevent accidental modification.

---

Method 2: Self-Update from a Running OS

If your CM4 is already booting from eMMC, USB, or network, you can enable self-update mode. However, this method carries a risk.

⚠️ Warning: Self-update mode does not update the bootloader atomically. If a power failure occurs during the EEPROM update, you could corrupt the EEPROM.

Why CM4 Disables rpi-eeprom-update by Default

On CM4, the rpi-eeprom-update service is disabled by default because the eMMC is not removable, and an invalid recovery.bin file could brick the system.

Enable Self-Update

1. Add the following to your config.txt or bootloader configuration:

ENABLE_SELF_UPDATE=1

1. Reboot the CM4. The bootloader will check for updates from the boot media (eMMC, USB MSD, or network boot).

---

Method 3: Update from Raspberry Pi OS (If Running)

If you have Raspberry Pi OS running on the CM4 and want to check the current EEPROM version:

# Check current EEPROM status
sudo rpi-eeprom-update

# Update to latest stable (only works if self-update is enabled or on supported platforms)
sudo rpi-eeprom-update -a

Note: On some platforms (e.g., Home Assistant Yellow with CM4), firmware updates via rpi-eeprom-update may be blocked with unsupported_boot_device. In such cases, use the rpiboot method instead.

---

Important Best Practices

Before deploying CM4 in production, Raspberry Pi recommends:

1. Select a specific bootloader release and verify every CM4 has that release.
2. Configure BOOT_ORDER to define the boot device priority (eMMC → USB → NVMe → Network, etc.).
3. Enable hardware write-protection (EEPROM_nWP pulled low) on production units to prevent unauthorized modification.

Example Bootloader Configuration

Create or edit boot.conf before flashing:

[all]
BOOT_UART=0
WAKE_ON_GPIO=1
POWER_OFF_ON_HALT=0
BOOT_ORDER=0xf2641   # eMMC → USB → NVMe → Network → Loop
ENABLE_SELF_UPDATE=1

Then use rpi-eeprom-config to apply it:

sudo rpi-eeprom-config --out pieeprom-new.bin --config boot.conf pieeprom.bin

---

Troubleshooting

Issue	Solution
rpiboot hangs or can't detect CM4	Check USB cable, ensure CM4 is powered, try a different USB port
EEPROM update succeeds but CM4 won't boot	Verify BOOT_ORDER is correct; newer silicon may require newer EEPROM (≥ 2026-01-09 for recent batches)
unsupported_boot_device error	Use rpiboot -d recovery method instead of OS-level update
Write-protected error	Ensure EEPROM_nWP is not pulled low during flashing

---

References

• Raspberry Pi Compute Module Documentation
• rpi-eeprom GitHub Releases
• usbboot GitHub Repository

Updating CM4 EEPROM Firmware with DeskPi Mini Cube

DIP Switch Configuration

The DeskPi Mini Cube has a 4-position DIP switch on the back that controls key CM4 signals. Here is the pinout:

Switch	Function	Description
1	USB OTG Pull UP	Enables USB OTG pull-up resistor
2	UNATTENDED	Unattended boot mode
3	EEPROM_nWP	EEPROM Write Protection (low = protected)
4	nRPIBOOT	eMMC Boot Disable (low = usbboot mode)

---

Step-by-Step: Flash EEPROM via USB (rpiboot)

1. Set DIP Switches for USB Boot Mode

To put the CM4 into rpiboot mode (required for EEPROM flashing), configure the switches before powering on:

Switch	Position	Reason
1	OFF	Not needed for EEPROM update
2	OFF	Not needed
3	OFF	Disable write-protection (EEPROM_nWP high → EEPROM writable)
4	ON	Enable nRPIBOOT (pull GPIO 40 low → ROM enters usbboot mode)

⚠️ Critical: Switch 4 must be ON before power is applied, and switch 3 must be OFF to allow EEPROM writing.

2. Connect Hardware

1. Connect a USB-C cable from the Mini Cube's USB-C port to your host PC (Linux/macOS/Windows).
2. Connect USB-C power to the Mini Cube's power input.
3. Power on the Mini Cube.

3. Run rpiboot on Host PC

On your host computer, clone and run the official usbboot tool:

# Linux / macOS
git clone --depth=1 https://github.com/raspberrypi/usbboot
cd usbboot
make

# Flash the EEPROM with the recovery firmware
sudo ./rpiboot -d recovery

This will write recovery/pieeprom.bin to the CM4's SPI EEPROM.

4. Custom EEPROM Configuration (Optional)

If you want to customize bootloader settings (e.g., BOOT_ORDER), edit recovery/boot.conf first, then regenerate the EEPROM image:

cd recovery
# Edit boot.conf as needed
./update-pieeprom.sh
cd ..
sudo ./rpiboot -d recovery

---

Step-by-Step: Normal Boot Mode (After Update)

Once the EEPROM is flashed, revert the DIP switches to boot from eMMC or NVMe:

Switch	Position
1	OFF
2	OFF
3	ON
4	OFF

Then power-cycle the Mini Cube.

---

Troubleshooting

Issue	Check
rpiboot cannot detect device	Verify switch 4 is ON before power-on; try a different USB cable/port
EEPROM write fails	Ensure switch 3 is OFF (write-protection disabled)
Green LED stays ON after disconnecting USB	Indicates nRPIBOOT GPIO is still high — check switch 4 is ON
Need to re-flash eMMC OS	Use sudo ./rpiboot -d mass-storage-gadget to mount eMMC as USB drive

---

Summary

Task	Switch 3 (EEPROM_nWP)	Switch 4 (nRPIBOOT)
Flash EEPROM	OFF (writable)	ON (usbboot mode)
Normal Boot	ON (protected)	OFF (boot from storage)

How to enable fan automatically?

** Assume that your operating system is Raspberry Pi OS (32bit/64bit) **

Official Fan setting

• Open a terminal and typing following command:

sudo raspi-config

Navigate to Performance Options -> P4 Fan -> Yes -> 14 -> 60 -> yes -> finish -> reboot Raspberry Pi.

The fan is support PWM signal control via GPIO14 which is physical pin 12(TXD), it will spinning when the CPU temperature is above 60 degree.

and also you can write your code to control the fan via GPIO14, sending PWM signal will trigger the fan spinning.

Control Fan manually

Demo code

• Here is a demo code for controlling fan speed by using python script.

 #!/usr/bin/python3

import RPi.GPIO as GPIO
import time
import subprocess

GPIO.setmode(GPIO.BCM)
GPIO.setup(14, GPIO.OUT)
pwm = GPIO.PWM(14,100)

print("\nPress Ctrl+C to quit \n")
dc = 0
pwm.start(dc)

try:
    while True:
        temp = subprocess.getoutput("vcgencmd measure_temp|sed 's/[^0-9.]//g'")
        if round(float(temp)) >= 45:
            dc = 100
            pwm.ChangeDutyCycle(dc)
            print("CPU Temp:",float(temp)," Fan duty cycle:",dc)
            time.sleep(180.0)
        if round(float(temp)) >= 40:
            dc = 85
            pwm.ChangeDutyCycle(dc)
            print("CPU Temp:",float(temp)," Fan duty cycle:",dc)
            time.sleep(120.0)
        else:
            dc = 70
            pwm.ChangeDutyCycle(dc)
            print("CPU Temp:",float(temp)," Fan duty cycle:",dc)
            time.sleep(60.00)

except KeyboardInterrupt:
    pwm.stop()
    GPIO.cleanup()
    print("Ctrl + C pressed -- Ending program")

Then execute it:

python3 fan_control.py

How to enable onboard RTC module?

NOTE: RTC battery sock type: ZH1.25 The battery dose not include in the package, additional purchase required!! * Step 1. Modify /boot/config.txt file and adding following parameter:

dtoverlay=i2c-rtc,pcf85063a,i2c_csi_dsi,addr=0x51

Save it and please reboot your Raspberry Pi.

• Step 2. Check if RTC module has been recognized by Raspberry Pi. Execute following command in a terminal:

  dmesg |grep i2c

  

  i2cdetect -y 10

  NOTE: if command not found, please install i2c-tools:

  sudo apt update
  sudo apt upgrade -y
  sudo apt -y install i2c-tools

  

• Step 3. Probe the module rtc-pcf85063 and check the kernel module status.

  modprobe rtc-pcf85063
  lsmod |grep rtc

  

• Step 4. Setting system date and sychronized system time to Hardware clock time.

** Check RTC time in command line.

cat /proc/driver/rtc

** Setting system time Syntax

date [-u|--utc|--universal] [MMDDhhmm[[CC]YY][.ss]]

For example:

sudo date -s 'tue oct 18 08:50:23 BST 2022'
or
sudo date 053118062023.22

It means setting system time to 2023.05.31 18:06:23.

** Sychronizing system time to HW clock time.

sudo hwclock -w

** Check RTC time and system time

sudo hwclock ; date

FAQ

• Q: Dose it support NVMe SSD booting? A: It has been tested, yes, it supports, but you may need to upgrade eeprom by using rpi-boot from official github repository.