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Internal Board Layout

IRIV PiControl Internal Board Layout

Internal board layout highlighting M.2 Key-M socket, Mini PCIe socket, RTC, secure authentication chip, and configuration switches.

Expansion Sockets​

M.2 Key-M Socket​

PCIe NVMe SSD support:

  • Gen 2 x1-lane PCIe interface
  • Supports 2230 and 2242 form factors
  • Bootable storage
  • M.2 SATA SSD is NOT supported

Installation:

  • Use M.2 Module Standoff for mounting 2230 or 2242 modules
  • Activity indicated by M.2 LED on front panel

Mini PCIe Socket​

Available signals:

  • USB 2.0
  • SPI

Important limitations:

  • PCIe signal is NOT available
  • Only USB 2.0 and SPI connections are routed to this socket
  • Power to socket controlled via GPIO6 (can be turned on/off programmatically)

Installation:

  • Use Mini PCIe Module Standoff for mounting modules

Onboard Devices​

Real-Time Clock (RTC)​

Chip: PCF85063A Interface: I2C Slave Address 0x51 Battery: CR2032 coin cell socket

  • Keeps RTC running when system is powered off
  • User-replaceable

Secure Authentication​

Chip: ATECC608B Interface: I2C Slave Address 0x60 Function: Crypto authentication for secure applications

Active Buzzer​

Control: GPIO19 Behavior: Beeps when GPIO19 output is HIGH Type: User-programmable active piezo buzzer

DIP Switches and Configuration​

RS485 Termination Resistor Enable Switch​

Function: Connect or disconnect 120Ω termination resistor for RS485 bus Location: Internal board, accessible after opening enclosure Usage: Enable termination at both ends of RS485 bus, disable for intermediate nodes

Analog Input Mode Switch​

Function: Configure analog inputs to measure voltage or current Modes:

  • Voltage Mode: 0-10V measurement
  • Current Mode: 0-20mA measurement

Important: The DIP switch must be set to current mode to enable the internal shunt resistor for 0-20mA measurements.

All four analog input channels share the same mode setting.

Boot/Debug Mode Switch​

Function: Select USB-C port operating mode Modes:

  • Boot: Flash OS image to CM4 eMMC
  • Debug: Access CM4 UART console

Power Protection​

4A Fuse​

Type: Replaceable fuse Rating: 4 Amp Function: Protects Terminal 1 power input from overcurrent Location: Internal board, accessible after opening enclosure

If the device fails to power up via Terminal 1, check and replace this fuse if necessary.

Wireless Configuration​

Wireless Disable Jumper​

Function: Disable WiFi or Bluetooth Method: Solder and short the jumper pads to disable wireless functions

Not specified in current sources: Separate jumpers for WiFi vs Bluetooth, or single jumper for both.

I2C Device Summary​

DeviceI2C AddressFunction
OLED Display (SSD1306)0x3CSystem status display
ADS1115 ADC0x48Analog input conversion
PCF85063A RTC0x51Real-time clock
ATECC608B0x60Secure authentication

Important Notes​

NVMe SSD Support​

  • Fully supported for Gen 2 x1-lane PCIe devices
  • Bootable from NVMe SSD
  • 2230 and 2242 form factors supported
  • SATA M.2 drives are NOT supported

Mini PCIe Limitations​

  • No PCIe signal available
  • Only USB 2.0 and SPI signals connected
  • Not suitable for PCIe-based expansion cards
  • Suitable for USB-based modules (e.g., 4G/LTE modems with USB interface)

Termination and Mode Switches​

  • RS485 termination: Enable only at bus endpoints
  • Analog mode switch: Applies to all four channels simultaneously
  • Current mode requires DIP switch ON to enable shunt resistor

Source(s):

  • IRIV PiControl CM4 User Manual, Rev 1.3, Nov 2025, Section 3.2