Key Connection Tip: When using COM port ribbon cable to connect RS-422/485 devices, it is necessary to connect the bottom D-Sub 5-pin cable (see Figure 2-8). Standard RS-232 serial port cable cannot be used for differential mode.
3.2 JP2: Clear CMOS
JP2 setting function
1-2 Short circuit (default) Normal operation
2-3 Short circuit clearing of CMOS content
When the BIOS settings are incorrect and unable to start, short circuit pin 2-3 of JP2 for about 2 seconds after power off, restore it to pin 1-2, and then power on again to restore the factory BIOS settings.
3.3 JP3: Watchdog Timer Output Mode
JP3 setting function
1-2 Short circuit (default) NMI (unshielded interrupt) trigger
2-3 Short circuit system reset trigger
After the watchdog timeout, it can choose to generate NMI (which can be captured and processed by software) or reset the system directly. By cooperating with software programming, a two-level protection mechanism can be implemented.
Chapter 4: Detailed Explanation of Key Interfaces and Connectors
4.1 System panel connector (CN1)
CN1 is a 20 pin needle arrangement that integrates all control signals from the front panel
Power LED (Pin1+5V, Pin5 PWLED): Indicates the system's power on status
Speaker (Pin2 SPKR, Pin4 BUZZ): connected to buzzer
Keyboard lock (Pin7 KBLOCK, Pin8+5V): Disable keyboard (short circuit lock)
Reset button (Pin9 GND, Pin10 RESET): Short circuit triggers hardware reset
ATX power switch (Pin15 PSON, Pin11/12 GND): Short circuit triggers soft power on/off
Hard drive LED (Pin14 HDDLED, Pin16+5V): Hard drive activity indicator
Power button (Pin18 PWRBT+5VSB, Pin20 PWRBT -): Connect to the front panel power button
4.2 Power Connection - ATX 12V Auxiliary Power Supply (CN4)
Key Warning: NuPRO-841 must be connected to CN4 (ATX 12V 4-pin power interface) in order to start properly. CN4 provides the+12V auxiliary power supply required by the CPU. If the connection is missed, the system will not be able to power on or run stably.
4.3 IDE interface (CN2 main IDE/CN5 secondary IDE)
Two 40 pin IDE interfaces (2.54mm spacing), supporting ATA-100, each interface can connect 2 devices (master/slave). Supports PIO mode and Ultra DMA/33.
4.4 Other I/O interfaces
CN6 parallel port: 26 pin pin arrangement, supports SPP/EPP/ECP mode
CN11 COM1: Standard DB9 male head, RS-232
CN12 IrDA: 5-pin infrared interface
CN13 LAN: RJ-45 interface (Intel 82562ET)
CN14 audio extension: 9-pin pin layout (with IP-ALCS20 audio daughter card)
CN15/CN16 USB 2.0: Two 9-pin pin headers, totaling 4 USB 2.0 ports
CN17 VGA: 15 pin D-Sub
CN19 PS/2 keyboard/mouse: 6-pin Mini DIN

Chapter 5: Detailed Explanation of BIOS Key Configuration Items
NuPRO-841 uses Award BIOS, press Del key to enter Setup when booting up.
5.1 Standard CMOS Features
IDE device configuration: Supports Auto detection and allows manual setting of Cylinder/Head/Recomp/Landing Zone/Sensor parameters. Manual prompt: "PRECOMP=65535 means NONE"
Access Mode: CHS/LBA/Large/Auto, LBA mode supports large capacity hard drives (>528MB)
Drive A/B: Soft drive type configuration, supporting 360K/1.2M/720K/1.44M/2.88M
Video:EGA/VGA/CGA 40/CGA 80/MONO
Halt On: Control POST error pause behavior
5.2 Advanced BIOS Features
Virus Warning: Protect the boot sector of the hard drive, it is recommended to disable it when running disk tools
CPU L1&L2 Cache: It is recommended to enable to accelerate memory access
Quick Power On Self Test: Enabled can shorten POST time
Boot Sequence: Set the boot device sequence (A, C, SCSI, etc.)
Boot Up NumLock Status: Set NumLock status at boot up
Gate A20 Option: Fast (chipset control)/Normal (keyboard controller control)
Security Option: Setup (password required to enter BIOS only)/System (password required to boot up and enter BIOS)
APIC Mode: Enable/Disable Advanced Programmable Interrupt Controller
5.3 Advanced Chipset Features
DRAM Timing Selectable: By SPD (automatically set according to SPD) or Manual (manually tuned)
CAS Latency Time:1.5/2/2.5
DRAM RAS# to CAS# Delay:2/3
Memory Frequency For:Auto/DDR266
System BIOS Cacheable: Enabled to cache BIOS ROM (F0000h-FFFFFh) for improved performance
Video BIOS Cacheable: Enabled to cache video BIOS
Memory Hold At 15M-16M: Reserve memory address space for ISA expansion cards, disabled by default
Delay Prior to Thermal: 4/8/16/32 minutes
AGP Aperture Size:4~256MB
5.4 Integrated Peripherals
On Chip Primary/Secondary PCI IDE: Enabled Enable IDE channel
IDE Primary/Secondary Master/Slave PIO: Auto or Mode 0-4 manual settings
IDE Primary/Secondary Master/Slave UDMA:Auto/Disabled
USB Controller/USB 2.0 Controller: Enable USB functionality
USB Keyboard Support: Set to Enabled when using a USB keyboard
AC97 Audio: Auto/Disabled (Auto required when using IP-ALCS20 daughter card)
Init Display First: PCI Slot/Onboard (onboard VGA priority or PCI graphics card priority)
IDE HDD Block Mode: Enabled Enable block mode transfer
Onboard Lan Boot ROM: Enable Network Boot (PXE)
Onboard Serial Port 1/2: Set serial port address and IRQ (3F8/IRQ4, 2F8/IRQ3, etc.)
UART Mode Select:Normal/IrDA/ASKIR
UR2 Duplex Mode: Half/Full (Infrared Half Duplex/Full Duplex)
Onboard Parallel Port:378/IRQ7、278/IRQ5、3BC/IRQ7、Disabled