DFI ADP253 Embedded 4" SBC
User's Manual
Published: July 11, 2025
Copyright and Trademarks
This publication contains information that is protected by copyright. No part of it may be reproduced in any form or by any means or used to make any transformation/adaptation without the prior written permission from the copyright holders.
This publication is provided for informational purposes only. DFI makes no representations or warranties with respect to the contents or use of this manual and specifically disclaims any express or implied warranties of merchantability or fitness for any particular purpose. The user will assume the entire risk of the use or the results of the use of this document. Further, DFI reserves the right to revise this publication and make changes to its contents at any time, without obligation to notify any person or entity of such revisions or changes.
Changes after the publication's first release will be based on the product's revision. The website will always provide the most updated information.
© 2023. All Rights Reserved.
Product names or trademarks appearing in this manual are for identification purpose only and are the properties of the respective owners.
FCC and DOC Statement on Class A
This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to Part 15 of the FCC rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a residential installation. This equipment generates, uses and can radiate radio frequency energy and, if not installed and used in accordance with the instruction manual, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:
- Reorient or relocate the receiving antenna.
- Increase the separation between the equipment and the receiver.
- Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.
- Consult the dealer or an experienced radio TV technician for help.
Notice:
- Changes or modifications not expressly approved by the party responsible for compliance could void the user's authority to operate the equipment.
- Shielded interface cables must be used in order to comply with the emission limits.
About this Manual
This manual can be retrieved from the website. The manual is subject to change and update without notice, and may be based on editions that do not resemble your actual products. Please visit the DFI website or contact DFI sales representatives for the latest editions.
Warranty
- Warranty does not cover damages or failures that arise from misuse of the product, inability to use the product, unauthorized replacement or alteration of components and product specifications.
- The warranty is void if the product has been subjected to physical abuse, improper installation, modification, accidents or unauthorized repair of the product.
- Unless otherwise instructed in this user's manual, the user may not, under any circumstances, attempt to perform service, adjustments or repairs on the product, whether in or out of warranty. It must be returned to the purchase point, factory or authorized service agency for all such work.
- DFI will not be liable for any indirect, special, incidental or consequential damages to the product that has been modified or altered.
About this Package
The package contains the following items. If any of these items are missing or damaged, please contact your dealer or sales representative for assistance.
- 1 ADP253 board
- 1 Heat sink (Height: 37mm)
- 1 Serial ATA data with power cable
Note: The items are subject to change in the developing stage. The product and accessories in the package may not come similar to the information listed above. This may differ in accordance with the sales region or models in which it was sold. For more information about the standard package in your region, please contact your dealer or sales representative.
Safety Precautions
Static Electricity Precautions
It is quite easy to inadvertently damage your PC, system board, components or devices even before installing them in your system unit. Static electrical discharge can damage computer components without causing any signs of physical damage. You must take extra care in handling them to ensure against electrostatic build-up.
- To prevent electrostatic build-up, leave the system board in its anti-static bag until you are ready to install it.
- Wear an antistatic wrist strap.
- Do all preparation work on a static-free surface.
- Hold the device only by its edges. Be careful not to touch any of the components, contacts or connections.
- Avoid touching the pins or contacts on all modules and connectors. Hold modules or connectors by their ends.
Important: Electrostatic discharge (ESD) can damage your processor, disk drive and other components. Perform the upgrade instruction procedures described at an ESD workstation only. If such a station is not available, you can provide some ESD protection by wearing an antistatic wrist strap and attaching it to a metal part of the system chassis. If a wrist strap is unavailable, establish and maintain contact with the system chassis throughout any procedures requiring ESD protection.
General Safety Precautions
- Use the correct DC / AC input voltage range.
- Unplug the power cord before removing the system chassis cover for installation or servicing. After installation or servicing, cover the system chassis before plugging in the power cord.
- There is danger of explosion if battery incorrectly replaced.
- Replace only with the same or equivalent specifications of batteries recommended by the manufacturer.
- Dispose of used batteries according to local ordinance.
- Keep this system away from humid environments.
- Make sure the system is placed or mounted correctly and stably to prevent the chance of dropping or falling which may cause damage.
- The openings on the system shall not be blocked and shall be kept in distance from other objects to make sure of proper air ventilation to protect the system from overheating.
- Dress the cables, especially the power cord, so they will not be stepped on, in contact with high temperature surfaces, or cause any tripping hazards.
- Do not place anything on top of the power cord. Use a power cord that has been approved for use with the system and is compliant with the voltage and current ranges required by the system's electrical specifications.
- If the system is to be unused or stored for a long time, disconnect it from the power source to avoid damage by transient overvoltage.
- If one of the following occurs, consult a service personnel: The power cord or plug is damaged; Liquid has penetrated the system; The system has been exposed to moisture; The system is not working properly; The system is physically damaged.
- The unit uses a three-wire ground cable which is equipped with a third pin to ground the unit and prevent electric shock. Do not defeat the purpose of this pin. If your outlet does not support this kind of plug, contact your electrician to replace the outlet.
- Disconnect the system from the electricity outlet before cleaning. Use a damp cloth for cleaning the surface. Do not use liquid or spray detergents for cleaning.
- Before connecting, make sure that the power supply voltage is correct. The device is connected to a power outlet which should be grounded connection.
The system may burn fingers while running. Wait for 30 minutes to handle electronic parts after power off.
Chapter 1 - Introduction
Specifications
| Category | Details |
|---|---|
| SYSTEM | Processor: 12th Gen Intel® Core™ Processors, BGA 1744 (Alder Lake-P, 15W) Intel® Core™ i7-1265UE Processor, 10C12T, 12M Cache, 1.7GHz (4.7GHz) Intel® Core™ i5-1245UE Processor, 10C12T, 12M Cache, 1.5GHz (4.4GHz) Intel® Core™ i3-1215UE Processor, 6C8T, 10M Cache, 1.2GHz (4.4GHz) Intel® Celeron® 7305E Processor, 5C5T, 8M Cache, 1.0GHz |
| Memory: 8GB On-board memory & one SO-DIMM DDR4 up to 32GB | |
| BIOS | Dual Channel DDR4 3200MHz AMI SPI 256Mbit (Supports UEFI boot only) |
| GRAPHICS | Controller: Intel® Iris® Xe Graphics Intel® UHD Graphics Feature: DirectX 12, Open GL 4.6, Vulkan 1.2 HW Decode: AV1, AVC/H.264, MJPEG, HEVC/H.265, VP9, SCC HW Encode: MJPEG, AVC/H.264, HEVC/H.265, VP9, SCC |
| Display: 1 x HDMI (Resolution up to 4096x2160 @60Hz) 1 x VGA/DP (Opt.) (VGA: Resolution up to 1920x1200 @60Hz, DP: Resolution up to 4096x2304 @60Hz) 2 x Type-C DP Alt. Mode |
|
| Multiple Displays | HDMI + VGA/DP (Optional) + Type-C DP Alt. Mode + Type-C DP Alt. Mode |
| EXPANSION | Interface: 1 x M.2 M Key 2280 (PCIex4/SATA) 1 x M.2 B Key 3042/3052 (USB3.0/USB2.0/PCIex1) 1 x M.2 E Key 2230 (CNVi/PCIex1/USB2.0) 1 x SIM slot for 4G/5G |
| AUDIO | Audio Codec: Realtek ALC888S |
| ETHERNET | Controller: 1 x Intel® I226-LM/IT (10/100/1000/2500Mbps) 2 x Intel® I226-LM/IT (10/100/1000Mbps) (Only Core i7/i5 supports iAMT) |
| REAR I/O | Ethernet: 1 x 2.5GbE (RJ-45) + 2 x GbE (RJ-45) Serial: COM 3: 1 x RS-232 (also supports an optional 8-bit DIO) USB: 4 x USB 3.2 Default: 2 x Type C + 2 x Type A connector Option: 4 x Type A connector Audio: 1 x Audio Combo Phone Jack (Line-out/Mic-in) Display: 1 x HDMI, 2 x Type-C DP Alt. Mode |
Dimensions
The ADP253 features a 4" SBC Form Factor with dimensions of 165mm (6.49") x 115mm (4.53"). The PCB thickness is 1.6mm. The top side height clearance is 16.34mm, and the bottom side height clearance is 3mm.
Block Diagram
The block diagram illustrates the system's architecture, showing connections between the Intel ULT SOC (Alder Lake-P), memory, various I/O controllers (IT6516BFN, Realtek ALC888, Intel I226-LM/IT), expansion slots (M.2, SIM), and interfaces like HDMI, VGA, DP, SATA, USB, and LAN.
Chapter 2 - Hardware Installations
Overview
This chapter covers hardware installation procedures, including jumper settings, pin assignments for various connectors, and installation of expansion modules.
Top View
The top view diagram shows the layout of key components and connectors on the ADP253 board, including COM ports, audio jacks, HDMI, USB ports, LAN ports, M.2 slots, SO-DIMM slot, and front panel headers.
Jumper Settings
COM Serial / DIO Switch (JP8 & JP9)
These jumpers configure the COM ports for Serial communication or Digital I/O (DIO) signals. The default setting is Serial COM Signal, while the optional setting is DIO Signal.
Pin Assignment
RTC Battery (J1)
| Pin | Assignment |
|---|---|
| 1 | V_BAT |
| 2 | GND |
SATA Power (CN8)
| Pin | Assignment |
|---|---|
| 1 | 12V |
| 2 | GND |
| 3 | GND |
| 4 | 5V |
SATA (J12)
| Pin | Assignment |
|---|---|
| 1 | GND |
| 2 | TX+ |
| 3 | TX- |
| 4 | GND |
| 5 | RX- |
| 6 | RX+ |
| 7 | GND |
Front Panel (JP10)
| Pin | Assignment | Pin | Assignment |
|---|---|---|---|
| 1 | PWR_BTN0 | 2 | V_SUS_LED |
| 3 | GND | 4 | SUS_LED# |
| 5 | SYS_RST0 | 6 | HD_LED# |
COM1 (CN49) & COM2 (CN50)
| Pin | RS232 | RS422 | RS485 |
|---|---|---|---|
| 1 | DCD- | TXD- | Data- |
| 2 | RD | TXD+ | Data+ |
| 3 | TD | RXD+ | N.C. |
| 4 | DTR- | RXD- | N.C. |
| 5 | GND | GND | GND |
| 6 | DSR- | N.C. | N.C. |
| 7 | RTS- | N.C. | N.C. |
| 8 | CTS- | N.C. | N.C. |
| 9 | RI- | N.C. | N.C. |
COM4 (CN52) & COM5 (J22) & COM6 (J23)
| Pin | Assignment | Pin | Assignment |
|---|---|---|---|
| 1 | MDCD- | 2 | MSIN- |
| 3 | MSO- | 4 | MDTR- |
| 5 | GND | 6 | MDSR- |
| 7 | MRTS- | 8 | MCTS- |
| 9 | MRI- | 10 | NC |
COM3/DIO (Optional) (CN51)
COM3 Pin Assignment
| Pin | Assignment | Pin | Assignment |
|---|---|---|---|
| 1 | MDCD- | 2 | MSIN- |
| 3 | MSO- | 4 | MDTR- |
| 5 | GND | 6 | MDSR- |
| 7 | MRTS- | 8 | MCTS- |
| 9 | MRI- | 10 | NC |
DIO Pin Assignment (Optional)
| Pin | Assignment | Pin | Assignment |
|---|---|---|---|
| 1 | DIOA0 | 2 | DIOA1 |
| 3 | DIOA2 | 4 | DIOA3 |
| 5 | GND | 6 | DIOA6 |
| 7 | DIOA7 | 8 | DIOA4 |
| 9 | DIOA5 |
Front Audio (AUJ1)
| Pin | Assignment | Pin | Assignment |
|---|---|---|---|
| 1 | Mic2-L | 2 | GND |
| 3 | Mic2-R | 4 | NC |
| 5 | Line2-R | 6 | Mic2-JD |
| 7 | GND | 8 | NC |
| 9 | Line2-L | 10 | Line2-JD |
USB2.0 (USB2_5/USB2_6) (UBJ2)
| Pin | Assignment | Pin | Assignment |
|---|---|---|---|
| 1 | 5V | 2 | 5V |
| 3 | USB2_5_N | 4 | USB2_6_N |
| 5 | USB2_5_P | 6 | USB2_6_P |
| 7 | GND | 8 | GND |
| 9 | NC | 10 | NC |
Expansion Slots
Installing the M.2 Module
Before installing the M.2 module into the M.2 socket, ensure the following safety cautions are observed:
- Make sure the PC and all other peripheral devices connected to it have been powered down.
- Disconnect all power cords and cables.
- Locate the M.2 socket on the system board.
- Make sure the notch on the card is aligned to the key on the socket.
- Make sure the standoff screw is removed from the standoff.
Follow these steps to install the card into the socket:
- Step 1: Insert the card into the socket at an angle, ensuring the notch and key are perfectly aligned.
- Step 2: Press the end of the card far from the socket down until it rests against the standoff.
- Step 3: Secure the card onto the standoff with a screw and a standoff screw until the gap between the card and the standoff closes. The card should be parallel to the board when correctly mounted.
Installing the SO-DIMM Module
Before installing the memory module, ensure the following safety cautions are followed:
- Make sure the PC and all other peripheral devices connected to it have been powered down.
- Disconnect all power cords and cables.
- Locate the SO-DIMM socket on the system board.
- Make sure the notch on the memory card is aligned to the key on the socket.
Follow these steps to install the memory card into the socket:
- Step 1: Insert the memory card into the slot at approximately a 45-degree angle horizontally, ensuring the notch and key are aligned. Press the card firmly into the socket with even pressure on both ends.
- Step 2: Press the end of the card down, ensuring the retention notch and clip align. If they do not align, remove and re-insert the card. Press the card all the way down.
- Step 3: The clips will snap automatically into the retention notches, locking the card in place. Verify that the clips are seated correctly. If not, pull the clips outward, release the card, and remount it.
Installing the Heatsink
The system board may come with a heatsink, including four stand-offs and four stand-off screws to secure the board and heatsink onto the chassis. The assembly is expected to be installed as illustrated below.
- Step 1: To avoid damage from excessive force, place the heatsink on a surface with the thermal pad side upwards. Remove any plastic film from the interface metal and apply thermal paste/adhesive if required. Place the motherboard on top of the heatsink, ensuring the CPU faces the interface metal side. Align the mounting holes and screw tight the mounting hole in the middle of the motherboard.
- Step 2: Screw the stand-offs onto the chassis. This step can be omitted if pre-installed stand-offs are present on the chassis.
- Step 3: Place the module combo onto the stand-offs, aligning the stand-off screw holes on the combo with those on the stand-offs.
- Step 4: Insert the provided stand-off screws into the screw holes of the combo and fasten them tightly with a screwdriver.
Note: Do not use excessive force or place direct pressure on the board, as it affects performance and may damage the motherboard.
Note: Chassis customization may vary installation procedures.
Chapter 3 - BIOS Settings
Overview
The BIOS is a program that handles basic communication between the CPU and peripherals. It contains codes for advanced system board features, allowing configuration and saving settings in battery-backed CMOS. Information in CMOS RAM remains unchanged unless a configuration change is made.
Note: BIOS screens may differ from the actual ones due to constant updates; these are for reference only.
Default Configuration
Most settings are predefined or automatically detected. Some settings may require manual adjustment based on your system configuration.
Entering the BIOS Setup Utility
The BIOS Setup Utility is operated via keyboard commands. After powering up, a BIOS message appears. Press the 'DEL' key when prompted to enter setup. If the message disappears, restart the system or press the 'Reset' button. Alternatively, press Ctrl + Alt + Del simultaneously.
Legends
| Keys | Function |
|---|---|
| Right / Left arrow | Move highlight left/right to select a menu |
| Up / Down arrow | Move highlight up/down between submenus or fields |
| <Enter> | Enter the highlighted submenu |
| + (plus key)/F6 | Scroll forward through values/options |
| - (minus key)/F5 | Scroll backward through values/options |
| <F1> | Display general help |
| <F2> | Display previous values |
| <F7> | Popup Boot Device List |
| <F9> | Optimized defaults |
| <F10> | Save and Exit |
| <Esc> | Return to previous menu |
Scroll Bar: Indicates more fields are available. Use arrow keys to scroll.
Submenu: The "" symbol indicates additional options are available. Press <Enter> to display the submenu.
Main
The Main menu is the initial screen upon entering the BIOS Setup Utility.
Advanced
The Advanced menu allows configuration for basic operation. Some settings are required by the system board, while others can improve performance or customize features.
Important: Setting incorrect field values may cause the system to malfunction.
System Date
Format: <month>, <date>, <year>. Use 'Tab' to switch fields and '-' or '+' to modify values.
System Time
Format: <hour>, <minute>, <second> (24-hour clock). Hours: 00-23, Minutes: 00-59, Seconds: 00-59.
CPU Configuration
- Intel (VMX) Virtualization Technology: When enabled, allows VMM to utilize additional hardware capabilities.
- Active Processor Cores: Select the number of cores to enable (all or 1).
- Hyper-threading: Enables Hyper-Threading technology for optimized OSes. Disable for others or for single-thread-per-core operation.
- AES: Enable or disable the AES function.
Note: Some fields may not be available depending on CPU support.
Power & Performance
Configure power management and performance settings.
PCH-FW Configuration
- ME State: Setting to 'Disabled' puts ME into a Temporarily Disabled Mode.
- ME Unconfig on RTC Clear: When disabled, ME is not unconfigured on RTC Clear.
- Firmware Update Configuration: Configure Management Engine Technology parameters.
Trusted Computing
- Security Device Support: Enables/disables BIOS support for security devices like TPM 2.0 for hardware-level security.
- Pending operation: Used to clear TPM encryption by selecting 'TPM Clear' and restarting. Not available if 'Security Device Support' is disabled.
IT8786 Super IO Configuration
- Watchdog Timer Unit: Select Second or Minute.
- SuperIO WatchDog Timer: Set timeout value from 0 (disabled) to 255.
Serial Port 1, 2 Configuration
- Serial Port: Enable or disable serial ports (COM).
- Device Settings: Configure I/O addresses and IRQ settings.
- Electrical Interface Mode: Select RS232.
Serial Port 3, 4 Configuration
- Serial Port: Enable or disable serial ports (COM).
- Device Settings: Configure I/O addresses and IRQ settings.
Serial Port 5, 6 Configuration
- Serial Port: Enable or disable serial ports (COM).
- Device Settings: Configure I/O addresses and IRQ settings.
IT8786 Hardware Monitor
Displays system health information: voltage readings, CPU and system temperatures, and fan speed readings.
Smart FAN Function
Fan speed moderation based on system temperature. Settings include Fan off temperature limit, Fan start temperature limit, Fan full speed temperature limit, and Fan start PWM.
Serial Port Console Redirection
Enabling Console Redirection for a COM port makes console redirection settings available. Configure serial settings for the current COM port.
Console Redirection Settings
- Terminal Type: Select VT100, VT100+, VT-UTF8, or ANSI.
- Bits per second: Select transmission speed (e.g., 115200).
- Data Bits: Select 7 or 8 bits.
- Parity: Select None, Even, Odd, Mark, or Space.
- Stop Bits: Select 1 or 2 bits.
- Flow Control: Select None or Hardware RTS/CTS (for RS485 mode, supported by COM1 only).
- VT-UTF8 Combo Key Support: Enable/disable for ANSI/VT100 terminals.
- Recorder Mode: Captures only text data.
- Resolution 100x31: Enables/disables extended terminal resolution.
- Putty Keypad: Select FunctionKey and KeyPad on Putty (VT100, LINUX, etc.).
ACPI Settings
- Wake System from S5 via RTC: Enable to automatically power up the system at a set time daily. Configure hour, minute, and second.
- State After G3: Specify system state after power failure (S0 State: auto power on; S5 State: soft-off; Last State: returns to previous state).
USB Configuration
- USB Mass Storage Driver Support: Enable/disable.
- Port 60/64 Emulation: Enables I/O port emulation for USB keyboard legacy support.
- USB transfer time-out: Sets time-out for Control, Bulk, and Interrupt transfers.
- Device reset time-out: Sets time-out for USB mass storage device start commands.
- Device power-up delay: Maximum time for a device to report itself to the Host Controller.
Network Stack Configuration
- Network Stack: Enable/disable UEFI network stack.
- IPv4 PXE/HTTP Support: Enable/disable IPv4 PXE/HTTP boot support.
- IPv6 PXE/HTTP Support: Enable/disable IPv6 PXE/HTTP boot support.
- PXE boot wait time: Sets wait time to abort PXE boot.
- Media detect count: Sets the number of times media presence is checked.
DFI WDT Configuration
- Watchdog Timer: Enable/disable Watchdog Timer.
USB Power Control
- USB Power Switch: Configures USB power behavior (5V_Dual for wake-up support, 5V for no wake-up support).
Tls Auth Configuration
- Server CA Configuration: Enroll or delete certificates.
- Client Cert Configuration: Configure client certificates.
Chipset
System Agent (SA) Configuration
- VMD setup menu: Access VMD Configuration settings.
- PCI Express Configuration: Access PCI Express Configuration settings.
- VT-d: Disable or enable VT-d.
PCH-IO Configuration
PCI Express Configuration
Select PCI Express channels (LAN1, LAN2, LAN3, M.2-E, M.2-B) to configure PCI Express Root Port settings.
SATA Configuration
- SATA Controller(s): Enable/disable the Serial ATA controller.
- SATA Speed: Select SATA speed generation (Auto, Gen1, Gen2, Gen3).
- Ports and Hot Plug: Enable/disable Serial ATA ports and hot plug function.
HD Audio Configuration
- HD Audio: Control detection of the HD Audio device (Disabled or Enabled).
Security
Administrator Password
Set an administrator password. Required for BIOS entry. Inputting nothing and pressing Enter clears the password.
Secure Boot
Secure Boot allows only OSes with authorized signatures to boot. Ensure 'Secure Boot' is '[Enabled]', Platform Key (PK) is enrolled, 'System Mode' is 'User', and CSM is disabled. Save configuration and restart. Status will show 'Active' when configured correctly.
- Secure Boot Mode: Standard or Custom. Custom allows manual key database modification.
- Restore Factory Keys: Loads OEM-defined factory defaults for keys and databases.
- Reset To Setup Mode: Clears NVRAM database, including keys and signatures.
- Key Management: Allows expert users to modify Secure Boot Policy variables.
Boot
- Setup Prompt Timeout: Sets the delay (in seconds) for setup activation key entry.
- Bootup NumLock State: Select On or Off for keyboard NumLock.
- Quiet Boot: Enable or disable the quiet boot option.
- Boot Option Priorities: Rearrange the system boot order.
- Fast Boot: Enable or disable fast boot.
Note: If 'Boot option filter' is set to 'UEFI and Legacy' or 'UEFI only', and 'Quiet Boot' is enabled, 'BGRT Logo' will display. Refer to Advanced > CSM Configuration for details.
Save & Exit
- Save Changes and Reset: Saves changes and restarts the system.
- Discard Changes and Reset: Discards changes and restarts the system.
- Restore Defaults: Loads optimized default values.
- Boot Override: Boots from a selected device for the current session only.
- Save Setting to file: Saves BIOS configuration to a USB flash device.
- Restore Setting from file: Restores BIOS configuration from a USB flash device.
Updating the BIOS
To update the BIOS, obtain the new BIOS file and a flash utility from technical support or a sales representative. Follow their specific instructions.
Notice: BIOS SPI ROM
- The Intel® Management Engine is integrated. The BIOS (SPI ROM) chip cannot be removed or used on other system boards of the same model due to safety concerns.
- The BIOS (SPI ROM) must be original factory equipment and cannot be used to replace chips from other system boards.
- Failure to follow these methods will prevent the Intel® Management Engine from updating and functioning correctly.
Note: Flash tools can update BIOS (SPI ROM) default configuration. When replacing the BIOS IC, ensure proper population and follow technical instructions regarding MAC address burning. Updating unique MAC addresses from manufacturing protects NVM immediately after power cycle. Users cannot update NVM or MAC addresses.
