Eurotech Appliances CPU-1461 - Manual (Page 39)

PC/104-Plus – CPU-1461 Module 39
PCI Advanced Page
This page can be used to specify some advanced PCI options like:
ƒ ISA IRQ
ƒ Latency Time (both for CPU and devices)
ISA IRQ
This option makes possible any assignment between an ISA IRQ (for the Interrupt Controller) and the four
PCI IRQ lines
A, B, C and D. Obviously not all the assignments are legal, but the Setup programs shows
only the available ISA interrupts.
Option Description Note
9 Routes PCI INT_n (n = A, B, C or D) to ISA IRQ 9 The IRQ# can be shared
10 Routes PCI INT_n (n = A, B, C or D) to ISA IRQ 10 The IRQ# can be shared
11 Routes PCI INT_n (n = A, B, C or D) to ISA IRQ 11 The IRQ# can be shared
12 Routes PCI INT_n (n = A, B, C or D) to ISA IRQ 12 The IRQ# can be shared
• Note: the ISA IRQ number can be shared among the PCI IRQ lines A, B, C and D.
Latency Time (Devices)
This Latency Time is the maximum time, expressed in clock cycle unit, that a generic PCI Device (like PCI
bus master) can hold the control of the PCI bus. The default value, generally, is 32.
Option Description Note
0..255 Latency time expressed in clock cycle units