1-40
Section 1 Specifications
1-4 I/O Address Assignment
1-4-1 Rules for assigning I/O addresses
In MICREX-SX series SPF, follow the rules below to assign I/O addresses.
(1) Unit No.
A number (1 to 6) is assigned to SPF expansion right side units, in their connected order. The number assigned to the main unit
is always “0” (zero). The front board is assigned “100” (fixed) as an independent unit and the expansion left side unit with “200”
(fixed).
<Example of unit No. assignment>
(2) Word No. and bit address
To each SPF unit, words starting from the word 0 (zero) are assigned for the number of words that the unit occupies. No same
word is assigned to both input and output. Therefore, for main units and expansion units with both inputs and outputs, words are
assigned first to inputs and then to outputs. The main unit occupies eight words of the I/O area (input: four words, output: four
words).
1-4-2 Example of address assignment
(1) Example of a system consisting only of a main unit (40 points)
Input : %IX (bit), %IW (word), %ID (double word)
Output : %QX (bit), %QW (word), %QD (double word)
Period
Prefix
Unit No.
Word No.
Bit address
(0 to 15)
Period
Expansion
left side unit
Unit No. 200
Expansion
right side unit
Unit No. 3
Expansion
right side unit
Unit No. 2
Expansion
right side unit
Unit No. 1
Main unit
Unit No. 0
Front board
Unit No. 100
%IW0.0
%IW0.1
%QW0.4
%IX0.0.0 to %IX0.0.15
%IX0.1.0 to %IX0.1.7
%QX0.4.0 to %QX0.4.15
0
15
Input: 24 points
Main unit with 40 points
Unit No. 0
Input: 24 points
output: 16 points
(Word address)
(Bit address)
Output: 16 points
