Руководство - руководство по программированию в среде U90 Ladder (англ.язык)
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According to the above example:
If MI 1 value is greater than the MI 3 value; then MB 51 will go to logic "1" (ON).
If MI 1 not greater than the MI 3 value; MB 51 will go to logic "0".
Less Than
The Less Than function block evaluates input A to see if its integer value is less than input B.
If input A is less than input B: power will flow through the function block.
If input A is not less than input B: power will not flow through the function block.
According to the above example:
If MI 1 value is less than constant integer 35; then MB 60 will go to logic "1" (ON).
If MI 1 value is not less than constant integer 35; MB 60 will go to logic "0" (OFF).
Not Equal
The Not Equal function block evaluates input A to see if its integer value is not equal to input B.
If input A is not equal to input B: power will flow through the function block.
If input A is equal to input B: power will not flow through the function block.
Input Operands A & B must be integer values: MI, SI or # constant integer value.
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According to the above example:
If MI 1 is not equal to MI 3; then MB 65 will go to logic "1" (ON).
If MI 1 is equal to MI 3; then MB 65 will go to logic "0" (OFF).
Using the Compare function
To use the Compare function:
1. Click Compare on the Standard toolbar. The Compare function list opens.
2. Select the desired Compare function.
3. Move the function block that appears to the desired net location.
4. Click to place the function block. The Select Operand and Address dialog box opens.
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5. Enter the Operands and Addresses in the dialog boxes and click OK.
6. The Compare function block appears with the selected Operands and Addresses.
Logic Functions
You perform logical functions in U90 Ladder by using logic function blocks. Function blocks are provided for:
AND
OR
XOR
The internal operation of a function block is transparent to the user. You input the two operands. The result is
automatically output by the function block
Input Operands A & B must be integer values: MI, SI or # constant integer value.
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Output Operand C may be a Memory Integer or a System Integer.
AND
Example
The AND logic function block can evaluate the state of two integers. If a bit is true (logic 1) in both input A and
B then the output C will be true (logic 1). If input A and B is false (logic 0) - the output C will be false (logic 0).
If either input A or B is false (logic 0) - the output C will be false (logic 0).
Input Operands A & B must be integer values: MI , SI or # constant integer value.
Output Operand C may be an MI or a SI.
AND can be used to mask out certain bits of an input integer not relevant to a given function.
Example:
If a clock function block uses the first bit of a 16-bit word to decide if a given time is A.M. or P.M., you can
mask out the other 15 bits. This will tell you if the current time is A.M. or P.M.
All of the non-relevant bits will be turned off (logic 0) expect the A.M. / P.M. bit.
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AND Example
You want to determine if an MI / SI value is an odd or an even number in your application.
An AND function between an integer A and #1:
If integer A is an even number then the result of the AND operation = #1.
If integer A is an odd number then the result of the AND operation = #0
OR
The OR logic function block can evaluate the state of two integers to see if either input A or B is true. If input A
OR B is true - the output C will be true (logic 1). If both input A and B are true (logic 1) - the output C will also
be true (logic 1).
Input Operands A & B must be integer values: MI , SI or # constant integer value.
Output Operand C may be a Memory Integer or a System Integer.
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XOR
The XOR logic function block can evaluate the state of two integers to see if input A and B are equal. If either
input A OR B is true - the output C will be true (logic 1). If both input A and B are true (logic 1) - the output C
will be false (logic 0). If both input A and B are false (logic 0) - the output C will be false (logic 0).
Input Operands A & B must be integer values: MI, SI or # constant integer value.
Output Operand C may be a Memory Integer or a System Integer.
Use XOR to recognize changes in an integer to check for integer bit corruption. If 2 integers are equal: the result
will return logic 0. If there has been bit corruption: the corrupted bit will return logic 1.
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Loops
Loops: Jump to Label
Loops in a Ladder project cause the program to jump over certain net(s), according to specific logic conditions.
A Loop contains a Jump element and a Label. When the Jump condition(s) is true, the project jumps to the
associated Label.
To create a Loop in your project:
1. Click Loop on the Ladder toolbar.
2. Select Set Label from the Loop menu. Place the cursor in the desired net and click.
3. The Edit Label box opens.
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4. Enter a Label name of up to eight characters.
5. The Label appears above the net.
6. Select Jump from the Loop menu.
7. Place the Jump in the desired place on the desired net.
8. Select Jump to... window appears.
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9. Select the desired Label name to which you want to jump. Click OK.
10. The Jump element appears with the selected Label name on the net.
According to the above example, if Ladder logic is true for net 4, the program will jump over nets 5 and 6 and
continue from net 7.
Important note: You must take care when creating Loops not to create an endless Loop. While you can place
Labels before a Jump condition and you can refer to a Label more than once, repeated referrals to a Label above
a Jump element can create an endless loop which will cause the controller to stop with an error message
"PROGRAM LOOP."
Loop functions are featured in the sample application, such as the applications ' Shortening scan time-jump'.
This application may be found by selecting Sample U90 Projects from the Help Menu.
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Math Functions
Math Functions
You perform mathematical functions in U90 Ladder by using math function blocks. Function blocks are
provided for:
Addition
Subtraction
Multiplication
Division
The internal operation of a function block is transparent to the user. You simply input the two operands. The
result is automatically output by the function block.
The example below shows the Add function block.
Input Operands A & B must be integer values: MI , SI or # constant integer value.
Output Operand C may be a Memory Integer or a System Integer.
You can use an Add function block to assign a real number value to an MI or SI.
Add