The address jumpers determine the address of the control block; the addresses and interrupts of the ports are
taken from the onboard EEPROM. The interrupt sharing register (mainly used in NT4) is referenced to the
address of Channel A.
The address bytes entered into the EEPROM represent address lines A9 thru A3. The easiest way to
determine the byte to write for a desired address is to divide the address by 8. For instance, a base address of
300 would be 300/8 = 60, an address of 308/8 = 61, and so on. (All addresses are in hex.)
Table 4-2:
ADDRESS JUMPERS
1st Digit
2nd Digit
Jumper Label
A9
A8
A7
A6
A5
--
Address Line Controlled
A9
A8
A7
A6
A5
A4
Hexadecimal Value
200
100
80
40
20
10
In order to read the address jumper setup, assign a binary “1" to jumpers that are not installed and a binary “0"
to jumpers installed. For example, as illustrated in the following table, jumper selection corresponds to binary
10 000x xxxx (hex 200). The “xxx” represents address lines A4, A3, A2, A1, and A0 used on the board to select
individual registers, as described in the
PROGRAMMING
section of this manual.
EXAMPLE ADDRESS SETUP
Jumper Label
A9
A8
A7
A6
A5
Conversion Factors
2
1
8
4
2
Jumper Installed
NO
YES
YES
YES
YES
Binary Representation
1
0
0
0
0
Hex Representation
2
0
Review the
ADDRESS SELECTION TABLE
carefully before selecting the board address. If the addresses of
two installed functions overlap you will experience unpredictable computer behavior.
Manual 104-COM-8S
16