DIGITAL INPUT/OUTPUT CARD IOD-144 USER MANUAL
4-1
ADDRESS SELECTION

The IOD-144 Input/Output Card occupies 24 bytes of I/O space. The card base address

can be selected anywhere within an I/O address range 000-3FF hex. If all 144 bits are

to be used in an AT-class computer, the base address can be set anywhere within the

address range hex 100-390 (except 1F0 through 1F8). If to be used in an XT-class

computer, the starting address can be as above except the lowest starting address is

200 hex.

However two installed options can not share the same address. If in doubt where to

assign the base address of the IOD-144, refer to the tables below and consult the

FINDBASE program on the utility diskette.

STANDARD ADDRESS ASSIGNMENTS FOR PC XT COMPUTERS

Hex Range Usage
000-00F
020-021
040-043
060-063
080-083
0AX
0CX
OEX
100-1FF
200-20F
210-217
220-24F
278-27F
2F0-2F7
2F8-2FF
300-31F
320-32F
378-37F
380-38C**
380-389**
3A0-3A9
3B0-3BF
3C0-3CF
3D0-3DF
3E0-3E7
3F0-3F7
3F8-3FF
DMA Chip 8237A-5
Interrupt 8259A
Timer 8253-5
PPI 8255A-5
DMA Page Register
NMI Mask Register
Reserved
Reserved
Not Usable
Game Control
Expansion Un it
Reserved
Reserved
Reserved
Asynchronous Comm'n (Secondary)
Prototype Card
Fixed Disk
Printer
SDLC Communications
Binary Synchronous Comm. (Secondary)
Binary Synchronous Comm. (Primary)
IBM Monochrome Display/Printer
Reserved
Color/Graphics
Reserved
Diskette
Asynchronous Comm'n (Primary)
** These options can not be used together - addresses overlap