Inputting Character Strings - Omron NT21 Reference Manual

Input of Numeric Values and Character Strings

3-7-2 Inputting Character Strings

memory table entry is notified to the host. It is not necessary to confirm the input
numeric value by pressing the ENT key or the
numeric key type input field is used.
With a thumbwheel switch, inputting of a numeric value using the input key –
control is not possible.
Setting a numeric value in the thumbwheel type input field.
– – – –
1 2 3 4
+ + + +
Press
– – – –
2 2 3 4
+ + + +
The relevant numeral increases by 1.
Changing a Sign
If a check mark is set for Display sign of a thumbwheel switch, the + and – keys
are used to change the sign if the keys in the sign display digit are pressed.
Pressing the + key changes the sign to + and pressing the – key changes the
sign to –.
Checking the Upper/Lower Limit
The PT has a function to check the correctness of an input numeric value to pre-
vent a numeric value outside the allowable range from being input so that the
input of an illegal value will not adversely affect the system.
The upper/lower (max./min.) limit check is executed in the timing indicated be-
low according to the type of a numeral setting input field.
For a thumbwheel switch, the check is executed each time the increment/decre-
ment key of each digit position is pressed.
With a thumbwheel switch, if n...n < m...m upper limit: 1n...n, lower limit: 0m...m
(n and m are arbitrary values at each digit), carry over and underflow are not pos-
sible at the highest digit position.
Example:
If the upper limit value and the lower limit value are 1200 and 201, respectively,
the numeric value can be changed only in the following range: from 201 to 999 if
an initial value is a 3-digit value and from 1000 to 1200 if an initial value is a 4-digit
value.
The reason for this is that the upper/lower (max./min.) limit check function does
not allow the numeric value at the highest digit position to change from 0 to 1 or
from 1 to 0.
To avoid this, set the upper and lower limit values so that n...n y m...m, or pro-
vide a touch switch separately to write a numeric value for carry over or under-
flow.
It won't be possible to change the numeric value with the increment and decre-
ment keys if the value is already outside of the range specified by the upper and
lower limits.
To input a character string, the touch switches input key – string and input key –
control are used. Basically, the input key – string and input key – control ar-
ranged on the same screen are used to directly input a character string into a
character string input field. It is also possible to use input key – string and input
key – control or a temporary input field registered for a window.
Registration of more than one character string input field in a screen is permitted.
To specify the objective input field among multiple input fields, either the input
key – control provided for shifting between input fields or a cursor moving key
should be used.
key, which is required when a
Numeral memory table entry
1 2 3 4
2 2 3 4
Section 3-7
Host
341