# Introduction

CM4 Sensing is an industrial computer designed for IoT & Data Acquisition applications based on Raspberry Pi Compute Module 4 (CM4 for short). It makes full use of the structural flexibility of CM4 to solve the heat dissipation problem of CPU, wireless module and PMU. The external antenna improves the reliability of wireless communication.

The system can be configured into 1GB/2GB/4GB/8GB RAM and 8GB/16GB/32GB eMMC, 2.4/5.8G dual-band WiFi and Bluetooth (optional) according to different applications, and it supports external antenna.

For application scenarios that require large data storage capacity, user can use eMMC to install the operating system and store the application data, at the same time, user can use SD card to store large user data, compare to the built-in eMMC memory, SD card can offer larger capacity and its cost is more effective.

CM4 Sensing provides 4G/LTE module, 4 channels RS485,1 channel RS232, 1 channel CAN, 1 channel Gigabit Ethernet port, alarm buzzer, battery-powered real-time clock.

The DSI interface of CM4 Sensing are fully compatible with Raspberry Pi4 Model B, supports Raspberry Pi official 7" touch display. A 5V/1.5A power output provides the power for Pi Display, the Standard HDMI interface can output 4K HD video.

CM4 Sensing provides 2 channels USB 2.0 and 1 channel Micro USB 2.0 interfaces, and Micro USB interface is used to update the system image.

The system supports +8V~28VDC* power input, the dimension of CM4 Sensing is 103*73*32mm, which is slightly larger than Pi4 Model B. The connectors come out from front and back end, a 103*73mm*5mm heat sink provides excellent cooling performance for CPU, wireless module and PMU, the whole system can work reliably in a high temperature environment. Based on our real testing in the lab, CM4 Sensing can work reliably at ambient temperature of -25~60°C.

Four M2.5 screw holes are reserved at the case bottom of the CM4 Sensing, which is convenient for users to install the CM4 Sensing on other equipment, it also supports DIN rail mounting and wall mounting.

# Hardware Specification

# Raspberry Pi CM4 Inside

  • Broadcom BCM2711
    • Quad-core, Cortex-A72, 1.5GHz ARM v8 64-bit CPU
    • Support H.264, H.265 decoding, Support 4Kp60 video play
    • Support H.264 encoding
    • Support OpenGL EL 3.0
  • DDR
    • LPDDR4, up to 3200MT/s
    • 1GB | 2GB | 4GB | 8GB
  • Dual Storage
    • 8GB | 16GB | 32GB eMMC
    • micro-SD Card for Data storage

# Dual Storage

  • eMMC for rootfs
  • 1x microSD Slot (for data storage)

# Display

  • 1x HDMI Type A
  • 1x DSI, Support Raspberry Pi official 7" Touch Display
  • 1x HDMI FPC

# Wired Interfaces

  • 1x 10/100M/1000Mbps Ethernet
  • 2x USB 2.0 Type A
  • 1x Micro USB 2.0(for eMMC Flashing and some USB Device Applications)

# Wireless

  • 1x 4G/LTE module(optional)
  • 1x 2.4G/5.8G WiFi, IEEE 802.11 b/g/n/ac
  • 1x Bluetooth 5.0, Support BLE
  • Optional certified WiFi/BT External antenna with Raspberry Pi CM4

# Industrial Interfaces

  • 4x RS485
  • 1x CAN
  • 1x RS232
  • 1x RTC with battery
  • 1x LED for Power Indicator
  • 1x LED for System status Indicator
  • 1x Buzzer

# Expansion Interfaces

  • Mini PCIe slot with 1-lane PCIe Gen2 and 1x USB 2.0 Host

# Power In

  • 8~28V DC Power Jack,Optional Phoenix terminal for power in

# Operating Temperature

  • -25 ~ 60°C

# Dimension

  • 103 mm(L) x 73 mm(W) x 32mm(H)

# Software

# Raspberry Pi Ecosystem

  • Compatible with Origin Raspberry Pi OS, support 32-bit and 64-bit OS
  • Support install and update BSP with apt-get
  • Support Kernel and OS Upgrade
  • Pre-installed Os in eMMC, ready-to-use

# Interface Diagram

# Top

# Bottom

# Ordering Code

# Specification

Feature Description
CPU Broadcom BCM2711 quad core, ARM Cortex-A72(ARM v8), 1.5GHz, 64-bit CPU
RAM 1GB / 2GB / 4GB / 8GB LPDDR4-3200
eMMC 8GB / 16GB / 32GB
SD Card eMMC for rootfs, micro SDCard for data storage
Ethernet 1x Gigabit Ethernet
WiFi / Bluetooth 2.4G / 5.8G Dual-band WiFi, Bluetooth 5.0, Support BLE
4G Support Quctel EC20/EC25 4G LTE module
HDMI 1x standard HDMI
HDMI FPC Touch Display 1x FPC HDMI, Support touch(USB) and brightness adjustment(PWM)
DSI 1x DSI, Support Raspberry Pi official 7" Touch Display
USB Host 2x USB 2.0 Type A, 1x USB 2.0 integrated in Mini PCIe, 1x USB micro-B for eMMC Flashing
RS485 4x RS485
RS232 1x RS232, Default is Linux System Serial console, can be configurated as normal serial port
CAN Bus 1x CAN
Mini PCIe 1-lane PCIe 2.0, up to 5Gbps, 1x USB 2.0 Host
RTC 1x RTC
Buzzer 1x Buzzer
DC Power Output 5V@1A, Could supply Raspberry Pi official 7" Touch Display
LED Indicator RED(Power), Green(System Status)
Power In 8V ~ 28V*
Dimension 103(L) x 73(W) x 32(H) mm
Case Metal Case, Support DIN rail mounting and wall mounting
Heat Sink A 103*73mm*5mm heat sink provides excellent cooling system
Antenna Optional certified WiFi/BT External antenna with Raspberry Pi CM4, Optional 4G Antenna
Operating Temperature -25 ~ 60°C
OS Compatible with Raspberry Pi OS, support 32-bit and 64-bit, Support install and update BSP with apt-get

# Product Photos

# CM4 Sensing with Case

# PCBA

* CM4 Sensing released Version 1.1 & 1.2, V1.1 supports 8V~18V DC input, V1.2 supports 8V~28V DC input.