Counter Types
Section 3-2
31
3-2-2
Linear Counter
Note
All of the functions listed in Section 1-3-2
can be used
if a Linear Counter is configured.
Configuring Linear Counters
A Linear Counter has the full counting range (=32 bits) available to count up- or
downwards over the positive and negative counting range between the Minimum
Count Limit and the Maximum Count Limit. By default the Minimum and Maximum
Count Limits are set to the maximum counting limits (i.e. –2,147,483,648 and
+2,147,483,647 respectively).
If the Counter Value goes above the Upper Count Limit or below the Lower Count
Limit an Overflow- and Underflow flag will be set respectively. These are reported
in CIO for the corresponding Counter.
On occurrence of an Overflow or Underflow, every Counter can be configured to
report a corresponding error-code. You can use Overflow/Underflow Error-Code
Generation to store Overflow and underflow errors in the EEPROM inside the Unit
(refer to section Section 5-2-3
Configuring Upper and
Lower Count Limits
The Upper Count Limit must be positive and the Lower Count Limit must be neg-
ative (zero is not allowed as Count Limit). To set the Maximum and Minimum
Count Limits refer to section the following:
CNT3:
CNT4:
m+50
m+70
Counter Type:
1 = Linear Counter
CNT1:
CNT2:
m+10
m+30
15 14 13 12 11 10 9
8
7
6
5
4
3
2
1
0
Counter Value
0
Up Counting
Down Counting
Underflow
Overflow
H
H
−
2,147,483,648
≤
Lowercount Limit
≤ −
1
80000000
≤
Lowercount Limit
≤
FFFFFFFF
≤
≤
≤
≤
H
1 Uppercount Limit +2,147,483,647
00000001 Uppercount Limit 7FFFFFFF
Upper Count Limit
CNT3:
CNT4:
m+53
m+73
m+54
m+74
m+55
m+75
m+56
m+76
Lower Count Limit
CNT1:
CNT2:
m+13
m+33
m+14
m+34
m+15
m+35
m+16
m+36
15 14 13 12 11 10 9
8
7
6
5
4
3
2
1
0
Set Upper Count Limit for Linear Counters between 00000001
H
and 7FFFFFFF
H
. By default
(=00000000
H
) the Upper Count Limit is equal to 7FFFFFFF
H
. Set Lower Count Limit for
Linear Counters between 80000000
H
and FFFFFFFF
H
. By default (=00000000) the Lower
Count Limit is equal to 80000000
H
.
