ADLINK NuPRO-935A Industrial Motherboard Debugging and Maintenance Guide

Enter configuration mode: Write 0x87 twice to port 0x2E (or 0x4E) and enter the IT8718 logical device configuration space.

Select logical device: Write to the 0x07 register to select the device number (usually 0x08).

Enable watchdog: Set the timer unit (seconds/minute) and count value.

Refresh (feed dog): Periodically write new values to the count register to prevent timeout.

Exit configuration mode: Write 0xAA to exit.

Practical suggestion: Create an independent dog feeding thread in the application to ensure timely system reset when the main loop freezes. To disable the watchdog, simply write the count value of 0.

Chapter 8: System Resource Troubleshooting - Interrupt Conflict and Memory Mapping

When peripherals such as ISA cards and serial port cards fail to function properly, it often involves IRQ or I/O address conflicts. Appendix B of the manual provides a detailed list of:

System memory mapping: including 640KB regular memory, 128KB video buffer, and high-end areas for BIOS/PCI expansion ROM (such as C0000-C7FFF for onboard VGA BIOS, CB800-C7FFF for Intel network card PXE ROM).

DMA channel: Traditional ISA devices may occupy DMA, but the IT8888 bridge does not support DMA. Therefore, if using an older ISA card, it is necessary to ensure that it does not require DMA.

IRQ allocation: In PIC mode, IRQ3~7、 Both 10-12 and 14-15 can be shared by PCI/ISA devices, but they need to be reserved in the BIOS for ISA devices. In APIC mode, there are more interrupt vectors (16~23) available for PCIe devices to use.

When encountering resource conflicts, the allocation strategy of IRQ/DMA can be manually adjusted in the BIOS "Advanced PCI/PnP Settings".

Chapter 9: Hardware Health Monitoring and Overheating Protection

Enter the BIOS' Hardware Health Configuration 'to view in real-time:

CPU/system temperature

CPU/system fan speed

Various voltages (Vcore,+3.3V,+5V,+12V, -12V, etc.)

If the temperature rises abnormally, check the radiator dust, fan operation status, and chassis air duct. BIOS also supports "CPU Warning Temperature" and "Shutdown Temperature" settings, which automatically shut down when the temperature exceeds a threshold to avoid permanent damage to components.

Chapter 10: Quick Troubleshooting Table for Common Malfunctions

Troubleshooting steps for possible causes of fault phenomena

There is no response when powered on, the fan does not turn, ATX 12V is not connected or CN1 wiring is incorrect. Check if CN7 is plugged in tightly and short-circuit the PSON and GND of CN1 to test if the power supply is started

There is power but no display. The CPU is not installed properly and the memory contact is poor. Reinstall the CPU and memory, clear the CMOS, and check the VGA cable

The system repeatedly restarts due to poor heat dissipation and insufficient power supply. Monitor BIOS temperature and replace high-power power supply

The operating system cannot find the hard disk SATA mode setting error. Change it to Compatible or Enhanced and check the SATA cable

Serial communication garbled jumper mode does not match the device. Reconfigure JP1-JP4 based on device type

The network port cannot recognize that LAN is disabled or PXE is not turned on in BIOS, and GbE LAN and GbE LAN Boot cannot be started

ISA card not working, driver not installed or IRQ conflicting. Install ISA driver and reserve IRQ for ISA in BIOS