American Megatrends 42 Series, User Manual

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ADVANCED CHIPSET SETUP Options
On Board Serial Port 1
Enables or disables serial port 1 on the Mark V Baby Screamer motherboard. The settings are I/O ports 3F8h - 3FFh, I/O ports
3E8h -3EFh, or Disabled .
If the configuration data stored in CMOS RAM is corrupted when the system is powered on, AMIBIOS automatically configures
onboard serial port 1 according to the presence or absence of serial ports on adapter cards in the expansion slots (offboard
serial ports). Autoconfiguration will only occur when CMOS RAM data is corrupted. The result for serial port 1 is:
If the Offboard
Serial Port is the Onboard Serial Port 1 is Autoconfigured as
None 3F8h Can be disabled or changed to 3E8h via
ADVANCED CHIPSET SETUP.
3F8h 3E8h Can be disabled via ADVANCED CHIPSET
SETUP. If changed to 3F8h, an I/O port address
conflict occurs.
3E8h 3F8h Can be disabled via ADVANCED CHIPSET
SETUP. If changed to 3E8h, an I/O port address
conflict occurs.
3F8h, 3E8h Disabled If changed to 3F8h or 3E8h, an I/O port address
conflict occurs.
P4 is serial port 1 on the Mark V Baby Screamer motherboard. If disabled through Setup, do not attach any device to P4 or to
any cable attached to P4. J22 is used to configure the interrupt request line (IRQ) for onboard serial port 1. The J22 settings
are:
Jumper Pins Shorted Description
J22 Pins 1-2 IRQ3 selected for onboard serial port 1.
J22 Pins 2-3 IRQ4 selected for onboard serial port 1 (Default).
If onboard serial port 1 is disabled, you can remove the jumper block from J22 to disable the onboard serial port 1 interrupt.