Hardware descriptions 
  A.5 System resources 
SIMATIC IPC677E 
Operating Instructions, 04/2019, A5E45117996-AA 
141 
A.5.4  Exclusive PCI hardware interrupt 
Applications demanding a high-performance interrupt require a high-speed hardware 
interrupt reaction. The PCI hardware interrupt should be used only by one resource in order 
to ensure high-speed reaction of the hardware.  
Exclusive interrupt on the device (APIC mode) 
 
IRQ assignments for Windows systems, (APIC mode) 
1, 2
1
1
1
1
1, 3
  Requirement: The modules in the PCI slots each require only one interrupt 
  Requirement: VGA and PCIexpress do not require an interrupt 
3)
  Requirement: VGA does not require an interrupt and Ethernet1 is disabled 
Assigning exclusive interrupts in the firmware (PIC mode) 
The interrupts are automatically assigned to the slots at system startup due to the default 
settings in system BIOS. 
Several slots may share the same interrupt, depending on the system configuration. This 
functionality is known as interrupt sharing. Exclusive interrupts are not available in PIC 
mode. Disable specific system resources in order to obtain exclusive interrupts. BIOS 
assigns the PIC interrupts at random during restart of the system.