System Operation
System Resources
The table below lists the system resources utilized by the circuits on Athena II.
Device
Default Address
ISA IRQ
ISA DMA Selectable Addresses
Serial Port COM1
I/O 0x3F8 – 0x3FF
3.4
–
2F8, 3E8, 2E8
Serial Port COM2
I/O 0x2F8 – 0x2FF
3,4
–
3F8, 3E8, 2E8
Serial Port COM3
I/O 0x3E8 – 0x3EF
3,4,5,6,9
–
–
Serial Port COM4
I/O 0x2E8 – 0x2EF
3,15
–
–
LPT Printer Port
I/O 0x378 – 0x37F
5,7
3
278, 3BC
IDE Controller A
I/O 0x1F0 – 0x1F7
14
–
–
A/D Circuit (when applicable)
I/O 0x280 – 0x28F
4,5,6
–
–
Watchdog Timer/Serial Port/FPGA
I/O 0x25C-0x25F
–
–
–
Ethernet
OS-dependent
OS-dependent
–
–
USB
OS-dependent
OS-dependent
–
–
Sound
OS-dependent
OS-dependent
–
–
Video
OS-dependent
OS-dependent
–
–
Note: In the preceding table, the selectable addresses are declared in CMOS BIOS.
Most of these resources are configurable and, in many cases, the Operating System alters these settings. The main
devices that are subject to this dynamic configuration are on-board Ethernet, sound, video, USB, and any PC/104-
Plus
cards that are in the system. These settings may also vary depending on what other devices are present in the
system. For example, adding a PC/104-
Plus
card may change the on-board Ethernet resources.
The serial port settings for COM3 and COM4 are jumper-selectable (J10), whereas the settings for COM1 and
COM2 are entirely software-configured in the BIOS.
Console Redirection to a Serial Port
In many applications without a local display and keyboard, it may be necessary to obtain keyboard and monitor
access to the CPU for configuration, file transfer, or other operations. Athena II supports this operation by enabling
keyboard input and character output onto a serial port, referred to as console redirection. A serial port on another
PC can be connected to the serial port on Athena II with a null modem cable, and a terminal emulation program,
such as HyperTerminal, can be used to establish the connection. The terminal program must be capable of
transmitting special characters including F2 (some programs or configurations trap special characters).
The default Athena II BIOS setting disables console redirection.
There are three possible configurations for console redirection:
•
POST-only (default)
•
Always On
•
Disabled
Diamond Systems Corporation
Athena II User Manual
Page 39
