Omron CQM1H - 08-2005, Operation Manual

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3-2 Bit Number Allocation
Two input words or four input words can be allocated to the Analog Input Unit,
which are specified with the DIP switch of the Analog Input Unit. Refer to page
81, DIP Switch Function for details.
3-2-1 Word Allocation
Input words are allocated according to the mounting order (from left to right) of
the Units. Refer to the CQM1H Programming Manual (W364), 3-2-3 I/O Alloca-
tion or the CQM1 Programming Manual (W228), 3-1 CQM1 Memory Area Func-
tions for details on I/O word allocation.
No word is allocated to the Analog Power Supply Unit. Mount the Analog Power
Supply Unit next to the Analog Input Unit either to the left or right.
Example: Four words are occupied.
Words 002 to 005 are used.
Word
CPU
000
001
006
100
IN 16 points
Sensor
Sensor
Sensor
Sensor
(Input 1)
(Input 2)
(Input 3)
(Input 4)
CQM1H/CQM1
IN 16 points IN 16 points
Out 16 points
P
S A
D I
P
S
PS : Power Supply Unit
CPU : CPU
IN
: Input Unit and terminals
OUT : Output Unit
IPS
: Analog Power Supply Unit
AD : Analog Input Unit
3-2-2 Bit Allocation
The following shows how the words allocated to the Analog Input Unit are used.
Any conversion data is stored in hexadecimal.
Bit
Word
15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00
n Input 1 conversion data
n + 1 Input 2 conversion data
n + 2 Input 3 conversion data
n + 3 Input 4 conversion data
Error Flag (Bit 13 of the First Word)
Bit 13 of the first word functions as an error flag. The error flag turns ON (be-
comes 1) if an invalid setting is made with the DIP switch (e.g., prohibiting the
conversion of all words) and the Analog Input Unit does not operate. If the input
range of input 1 is –10 to 10 V and the conversion data of input 1 is negative,
however, this bit turns ON because 2’s complement is used to indicate the nega-
tive data. If bit 15 of the first word is OFF and bit 13 is ON, it indicates an error.
Broken Wire Detection Flag (Bit 12 of Each Word)
If the input range of the Analog Input Unit is 1 to 5 V or 4 to 20 mA and the voltage
of an input is less than approximately 0.95 V or the current of an input is less than
approximately 3.8 mA, the broken wire detecting function of the Analog Input
Unit will be activated and the bit 12 of the corresponding word will turn ON (the bit
will become 1).
Bit Number Allocation
Section 3-2