ADLINK Express-BASE7 Carrier Board Quick Deployment and Debugging Guide

ADLINK Express-BASE7 Carrier Board Quick Deployment and Debugging Guide

Why choose COM Express carrier solution

In the fields of industrial control, edge computing and communication equipment, the product forms are diverse, and it is time-consuming and laborious to completely customize the motherboard. The modular design of COM Express integrates core processors, memory, and critical I/O on standardized modules, while peripheral interfaces are implemented through custom carrier boards, retaining customization flexibility and significantly reducing development cycles. ADLINK's Express-BASE7 is a standard ATX sized carrier board designed specifically for COM Express Type 7 modules, supporting up to 32 PCIe channels and four 10GbE networks, making it an ideal prototype platform for building high-performance edge servers.

This article is based on the Express-BASE7 user manual, providing engineers with a practical guide that can be directly implemented from hardware deployment, power configuration, jumper settings, debugging methods to common problems.

Quick Overview of Core Features

Express-BASE7 follows the PICMG COM. 0 Rev. 3.0 specification and supports Type 7 modules in Basic and Compact sizes. Its key features include:

32 PCIe lanes: flexibly allocated through one x16 dedicated slot (for 10GbE daughter cards), one standard x16 slot, and two x8 slots.

10GbE Expansion: A dedicated x16 slot (non-standard PCIe signal) can convert the module's four 10GBASE-KR channels into SFP+fiber or BASE-T copper cable interfaces, compatible with SFP+cards or BASE-T cards.

NC-SI and IPMI BMC: The onboard MiniBMC supports remote management (power status, voltage monitoring, power on/off, serial port redirection), and the functions are customized according to the project.

LPC Super I/O: Using Winbond W83627DHG-PT, it provides traditional COM ports and PS/2 keyboard and mouse to compensate for the lack of Super I/O in the module.

Secondary SPI BIOS: The BIOS on the module or the backup SPI Flash on the carrier board can be selected through jumper cables for easy testing of new versions or recovery of damaged BIOS.

Integrated debugging port: Two bit POST code display and four bit address display, supporting single step execution mode, greatly facilitating low-level debugging.

Mechanical and Layout

The board adopts standard ATX size (305mm × 244mm), and the key positioning holes are precisely positioned with COM Express connectors (AB and CD sockets). In terms of layout, the power connector is located on the right side of the board, the PCIe slots are concentrated in the middle and lower parts, and the debugging interfaces and jumpers are distributed at the edge of the board for easy operation.

Detailed explanation of connectors and jumpers

4.1 Power connectors and strategies

Express-BASE7 uses two power inputs:

CN1 (ATX 24 pin): Provides power to peripheral circuits (Super I/O, fans, USB, etc.) on the motherboard.

CN5 (ATX 12V 4-pin): Specially designed to provide 12V power supply for COM Express modules. The system must be connected to both interfaces simultaneously in order to start up properly. Attention: Even when using a 20 pin ATX power supply, the 4-pin plug must be inserted into the CN5 and must not be plugged in incorrectly.

There are two power modes, ATX and AT, which can be selected through jumper JP1 (1-2 for ATX, 2-3 for AT). In AT mode, the PS-ON # signal is directly grounded, and it starts up immediately upon power on (without standby). The specific power strategy depends on the power type and jumper combination. The manual provides four combination tables (ATX power+ATX mode, ATX power+AT mode, etc.).

Other power related jumpers:

JP2 (PS-ON # signal source): Select SUS_S3 # (default) or SUS_S5 # from the module to determine the PS-ON # behavior of the system during sleep/shutdown.

JP3 (5VSB source): Select 5V standby voltage from the carrier board itself, ATX power supply, or module itself.

JP34 (12V to module in S3/S5 state): By default, 12V is cut off in S3/S5, and can be jumper to provide constant power supply.

Engineering tip: Before powering on for the first time, be sure to confirm the JP1 and JP2 settings, especially when using AT power, to avoid accidental forced power on or inability to shut down.

4.2 COM Express Board to Board Connectors (AB/CD)

Two 220 pin connectors fully comply with the Type 7 definition. The CD connector carries 32 PCIe lanes, four 10GBASE-KR, SATA, USB 3.0, and NC-SI signals. AB connectors include GbE, LPC, SMBus, power management, etc. Please refer to Table 1 in the manual for all pin definitions. Engineers should strictly follow this when designing custom carrier boards.

4.3 PCIe slot allocation

PCIEKR (Dedicated 10GbE Slot): A non-standard x16 slot, signal connected to a 10GBASE-KR differential pair of modules, used to insert SFP+or BASE-T daughter cards provided by ADLINK. This slot provides signals such as I2C, interrupt, and PHY control simultaneously.

PCIE 16 (standard x16): Adjacent to PCIEKR, but with a standard PCIe x16 signal (PCIe Lane 15-31 from module).

PCIE 1 (x8): from Lane 0-7.

PCIE 2 (x8): from Lane 8-15.