Figure c-1. floating point examples – Micromod Micro-DCI: 53SL6000 Single Loop Controller User Manual
Page 127

Table C-5. Datapoint Addresses
Type
Base
Addr
Address
Calculation
H
09CF
H
Address =
H
Base + (5 X
H
Number)
= 9CF
H
+ (5 X
H
Number)
Address example: H001 location
9CF
H
+ (5 X 1) = 9CF
H
+ 5
D
= 9CF
H
+
5
H
= 9D4
H
.
Table C-5. Datapoint Addresses
Type
Base
Addr
Address
Calculation
A
and
F
09E8
H
Address = A Base + (10 X Number)
= 9E8
H
+ (10 X Number)
Address example: A015 location
9E8
H
+ (10 X 15) =
9E8
H
+ 150
D
= 9E8
H
+ 96
H
A7E
H
.
Address = F Base + (5 X Number)
= 9E8
H
+ (5 X Number)
(For F data type within A database.)
2
0
sign bit
2
-1
0.5
2
-2
0.25
2
-3
0.125
2
-4
0.0625
2
-5
0.03125
2
-6
0.015625
2
-7
0.0078125
2
-8
0.00390625
2
-9
0.001953125
2
-10
0.0009765625
2
-11
0.00048828125
2
-12
0.000244140625
2
-13
0.0001220703125
2
-14
0.00006103515625
2
-15
0.00003051757813
2
-16
0.00001525878906
2
-17
0.000007629394531
2
-18
0.000003814697266
2
-19
0.000001907348633
2
-20
0.0000009536743164
2
-21
0.0000004768371582
2
-22
0.0000002384185791
2
-23
0.0000001192092895
2
-24
0.00000005960464477
2
-25
0.00000002980232239
2
-26
0.00000001490116119
2
-27
0.000000007450580596
2
-28
0.000000003725290298
2
-29
0.000000001862645149
2
-30
0.0000000009313225745
2
-31
0.0000000004656612873
2
-32
0.0000000002328306436
Two examples of C and H floating point value calculations.
(Note: calculator values are approximations of the controller values given in the
first line of each example.)
Example 1:
Value as nearest C
→
1111.0000000000000000
→
45 70 0B
Calculator check (calculator numbers are rounded):
0100 0101 0111 0000 x 2
0B
or 0100 0101 0111 0000 x 2
11
(Sum of Exponents -1, -5, -7, -9, -10, -11) x 2
11
= .5 + .03125 + .0078125 + .001953125 + .0009765625 + .00048828125
x 2048
= 0.542480468 x 2048 = 1110.999998
≈
1111
Value as nearest H
→
1111.0000000000000000
→
45 70 00 00 0B
Calculator check (calculator numbers are rounded):
0100 0101 0111 0000 0000 0000 0000 0000 x 2
0B
or
0100 0101 0111 0000 0000 0000 0000 0000 x 2
11
(Sum of Exponents -1, -5, -7, -9, -10, -11) x 2
11
= .5 + .03125 + .0078125 + .001953125 + .0009765625 + .00048828125
+ .0 + .0 + .0 + .0 + .0 x 2048
= 0.542480468 x 2048 = 1110.999998
≈
1111
Example 2:
Value as nearest C
→
0.09999847412109375
→
66 66 FD
Calculator check (calculator numbers are rounded):
0110 0110 0110 0110 x 2
FD
or 0110 0110 0110 0110 x 2
-3
(Sum of Exponents -1, -2, -5, -6, -9, -10, -13, -14) x 2
-3
= .5 + .25 + .03125 + .015625 + .001953125 + .0009765625 +
.0001220703125 + .00006103515625 x 0.125
= 0.799987792. x 0.125 = 0.099998474
≈
0.1
Value as nearest H
→
0.09999999997671694
→
66 66 66 66 FD
Calculator check (calculator numbers are rounded):
0110 0110 0110 0110 0110 0110 0110 0110 x 2
FD
or
0110 0110 0110 0110 0110 0110 0110 0110 x 2
-3
(Sum of Exponents -1, -2, -5, -6, -9, -10, -13, -14, -17, -18, -21, -22, -25, -26
-29, -30) x 2
-3
= .5 + .25 + .03125 + .015625 + .00195313 + .00097656 +.00012207 +
.000061035 + .00000763 + .00000382 + .000000468 + .000000238 +
.0000000298 + .0000000149 + .00000000186 + .000000000931 x 0.125
= 0.799999998491 x 0.125 = 0.0999999998 which is close to the
Figure C-1. Floating Point Examples
53SL6000 Instruction Manual
Appendix C. Datalink Protocol
C-4