DFI HD636-H81CS Industrial Motherboard Deployment and Debugging

3.6 SATA DOM Power Selection (JP11)

SATA port 0 provides sufficient space to install SATA DOM (Disk On Module), and JP11 selects its power supply voltage (+5V or+5V_standby), with a default of+5V.

3.7 Digital I/O (DIO) power and output status selection

JP13 selects DIO signal power supply (+5V or+5V_standby).

JP7 and JP12 respectively control the pull-up/pull-down states of the DIO pins to adapt to the level requirements of different peripherals.

Detailed explanation of rear I/O interface and internal connectors

4.1 Rear I/O panel

Provide PS/2 mouse/keyboard, 2 COM ports (COM1/2), 1 HDMI, 1 VGA, 2 RJ45 LAN (Intel 82574L), 2 USB 3.0, 2 USB 2.0, and audio jack (Line in/Line out/Mic in).

4.2 Internal Expansion Interface

PCIe x16 Gen2 slot: used for discrete graphics cards or high-performance expansion cards.

Two PCIe x4 Gen2 slots (actual x2 signal).

4 PCI slots (PCI 2.3), suitable for older industrial I/O cards.

4 SATA interfaces (SATA 0/1 is 6Gb/s, SATA 4/5 is 3Gb/s), supporting AHCI.

6 additional serial port pins (COM3~COM8, with COM8 configurable mode).

8-bit digital I/O pin (including power output).

LPC debugging port, front panel pin layout, parallel port, S/PDIF, etc.

Important notice: Vertical USB (USB2) and USB pin bank (USB2-3) physically share the same location, and vertical USB is used by default. At this time, USB3 pin bank is invalid (note in BIOS).

BIOS key settings optimization

When entering BIOS (press Del to power on), pay attention to the following options:

5.1 Advanced Menu

CPU configuration: Hyper Threading (recommended to turn on Windows/Linux and turn off outdated RTOS), Intel Virtualization Technology (if using a virtual machine to turn it on), EIST (energy-saving technology, recommended to turn it on in industrial control scenarios to reduce power consumption).

SATA configuration: If using SSD, it is strongly recommended to set SATA Mode Selection to AHCI (supporting NCQ and hot swappable) instead of IDE mode. Each port can be individually enabled/disabled and hot swappable.

USB configuration: Legacy USB Support recommends setting it to Enabled (to ensure USB keyboard recognition under DOS). XHCI Hand off remains enabled for the operating system to take over the USB 3.0 controller.

Super IO configuration: Here, the Restore AC Power Loss state can be set - Power Off, Power On, or Last State. In addition, the watchdog timer unit (seconds/minute) and timeout value are set here.

Serial port configuration: Set IO/IRQ for COM1~COM8 separately and enable/disable them. COM8 needs to be compatible with hardware jumpers.

5.2 Chipset Menu

System Agent (SA) Configuration: Graphics Card Selection (Primary Display) - If using a discrete graphics card, select PEG, and if using integrated display, select IGFX. DVMT pre allocated memory (fixed) and total memory size can be adjusted as needed.

PCH-IO configuration: The onboard dual Intel 82574L network card controller can be enabled/disabled here. The PCIe root port speed can be set to Auto/Gen1/Gen2.

5.3 Boot menu

Quiet Boot: It is recommended to disable it during the debugging phase to display POST self-test information.

CSM parameter: If you need to start a traditional Legacy device (such as DOS or old versions of Windows), you need to set Launch CSM to Enabled and select UEFI/Legacy priority based on the device type.

Driver and tool software installation

Chapter 4 of the manual lists the driver installation sequence for Windows 7/8/XP:

Intel chipset driver (must be installed first).

Graphics card driver (Intel HD Graphics).

Intel LAN driver (for Windows XP, manually specify the driver file path, see detailed steps on pages 59-61 of the manual).

Intel Management Engine driver.

Intel Rapid Storage Technology (for SATA AHCI/RAID management).

DFI Utility - Provides board information, hardware health monitoring, watchdog settings, and digital I/O control interface.

NuVton SIO (Super IO driver).

TPM drivers and tools (optional).

It is recommended to install the operating system in the order mentioned above to avoid device resource conflicts.

Digital I/O (DIO) Programming Guide

The motherboard provides 8-bit digital I/O (DIO0~DIO7), controlled through the I2C interface (slave device address 0x42). The complete register definition and C language example code are provided on pages 71-72 of the manual.

7.1 Register Definition

Input port register (address 0x00): reflects the current level of the pin (read-only).

Output port register (address 0x01): controls the output level (write operation).

Polarity reversal register (address 0x02): performs logical inversion on the input pin.

Configure register (address 0x03): Each bit is 1 for input, 0 for output (default all 1s means all inputs).

7.2 Programming Steps

Write a value to the configuration register and set the specified pin as the output (corresponding bit reset).

Write high/low levels to the output register.

If you need to read input, first ensure that the pin is configured as input, and then read the input register.

The example functions provided in the manual include GpioConfig (setting direction), GpioOut (output), and GpioIn (input). Engineers can directly reference these codes and implement DIO control through I2C read-write functions for driving relays, LEDs, or reading sensor status.