Rockwell Automation 1772-L8_LW_LWP_LX_LXP,D17726.5.8 User Manual - Manual (Page 195)

EAF Logarithmic, Trigonometric
and FIFO Instructions
Chapter 15
15-2
Figure 15.1
EAF One Operand Word and Digit Format in the Data Table
17 16 15 14 10 7 4 3 Data
0
S Digit 1 Digit 2 Digit 3
Digit 4
Digit 7
Digit 10
Digit 5
Digit 8
Digit 11
Digit 6
Digit 9
Digit 12
Operand
MSD
LSD
b
d
g
k
Result
Address
Result
r
r+1
r+2
r+3
10363-I
13
X S 0 O/U
Address
The Operand and the Result words have the format xxx xxx . xxx xxx.
You can enter them from the keyboard of your 1770-T3 terminal or
through ladder diagram instructions.
If you select a data address (inside the EAF) other than 010 for the
Operand, you can locate the data anywhere in your data table. However,
you must select four consecutive data table addresses (Figure 15.2).
If you choose to enter the default address (010) as the Data Address inside
the EAF instruction, the processor seeks its data from the Get instructions
in the Operand rung. Address 010 will not be altered or used by this
instruction. The Get instruction must be located in the rung immediately
before the EAF instruction. You may select up to four data table addresses
(Figure 15.2). You can locate the Result word anywhere in your program.
However, you must select four consecutive addresses for the result. If you
select an address of 060 for the Result, the EAF automatically reserves the
next three higher addresses.
To enter the number ABC use only one Get or one data table word.
Important: If there is only one Get, the value is placed immediately to the
left of the decimal point.
––––[G]––– xxx ABC . xxx xxx
+/– ABC