Octagon 5266, Справочное руководство

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Chapter 17: CPU clock and ISA bus interrupt routing
CPU clock speed
The CPU clock speed can be configured to run at 400 MHz or 500 MHz. The
CPU/GLIU field in the BIOS Setup Custom Configuration sets the speed. The
default is 500 MHz.
ISA bus and onboard interrupt routing
The 5266 provides for flexible routing of interrupts that originate from the ISA bus
and onboard source. The interrupt routing provides flexibility to the interrupt
structure, allowing the lower-ordered ISA interrupts to be connected to the unused
higher-ordered interrupts. Caution must be used when configuring the jumper
options. The application software must also be aware of the interrupt that is set for
the particular resource.
Jumper blocks W4 and W5 allow the source interrupt to be routed to the
appropriate destination.
Table 17–1 shows the jumper settings for the ISA bus interrupts, as well as the
default configuration for each of the interrupts. The ISA bus interrupts that can be
routed are:
Bus IRQ3
Bus IRQ4
Bus IRQ6
Bus IRQ7
Table 17–2 shows the jumper settings for the onboard interrupts, as well as the
default configuration for each of the interrupts. The onboard interrupts that can be
routed are:
Serial Port A IRQ (COM1)
Serial Port B IRQ (COM2)
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