Doc. No. 1512-1-HAA-1003-1-2.0
Rev. 1.0 (Released)
November 8, 1997
Copyright (C) Odin TeleSystems Inc., 1997
7(15)
Balder-8S 2.0 Installation Guide
Configuring Balder-8S
5.4 Setting the I/O Base Address
Balder-8S requires access to a 32-byte long I/O address space, the base address of
which can be set to any even 32-byte boundary within the range 0000h - 03FFh. Since
different PCs are equipped with different hardware, the address space that should be
selected is PC specific. The factory default for the Balder-8S board is I/O base address
0280h (i.e. Balder-8S will use 32 bytes in I/O ports 0280h through 029Fh). This needs
to be changed if the PC already contains hardware (e.g. LAN adapters, drive control-
lers, or serial port boards) which use this address area. Consult the documentation for
the corresponding hardware to determine what I/O addresses are free for use by the
Balder-8S board (see also Table 2, “IO base address settings.,” on page 7)
If more than one Balder-8S is installed in one PC, the different boards should be set to
the same I/O address. The board number then determines in which 1024 (400h) byte
segment the board places its I/O address space. For example, if a board is set to num-
ber 3 and I/O address 280h the board will occupy I/O address (3 * 400h + 280h) to
(3*400h + 280h + 31). There is normally no need to worry about these calculations
unless the PC is equipped with boards that use I/O addresses beyond 400h, which is
uncommon. In virtually all cases it is sufficient to choose an I/O address that does not
conflict with the I/O address of other boards and then set each board to have unique
board numbers (Section 5.3 on page 6).
The I/O base address is set with switches S1-S4 in dip-switch SW1, as listed in Table
2.
TABLE 2. IO base address settings.
IO Base
Address
S5
S4
S3
S2
S1
Comment
0200H
Off
On
On
On
On
Not recommended
1
0220H
Off
On
On
On
Off
0240H
Off
On
On
Off
On
0260H
Off
On
On
Off
Off
Not recommended
2
0280H
Off
On
Off
On
On
Balder-8S default
02A0H
Off
On
Off
On
Off
02C0H
Off
On
Off
Off
On
02E0H
Off
On
Off
Off
Off
Not recommended
3
0300H
Off
Off
On
On
On
Default for most other boards
0320H
Off
Off
On
On
Off
0340H
Off
Off
On
Off
On
0360H
Off
Off
On
Off
Off
Not recommended
4
0380H
Off
Off
Off
On
On
03A0H
Off
Off
Off
On
Off
Not recommended
5
03C0H
Off
Off
Off
Off
On
Not recommended
6
