Rockwell Automation 2755 Enhanced Decoder Series B - Manual (Page 125)

9–3 Configuration: AUX and LCD Display Parameters
Publication 2755-833
Scroll LCD
Field Type Options
Select
No
Yes
Enables or disables scrolling of the LCD display. The default of No
disables scrolling and formats the LCD as a single line, 40 character
display. Each new entry overwrites all positions.
Note: Newly displayed data will overwrite existing display data
from the lowest position specified to the end of the display with
blanks, so plan your LCD display parameters carefully. For example,
messages written from the host to position 1 would not be
overwritten by the decoder if the lowest position specified for LCD
display was 21.
Select Yes to enable scrolling. With scrolling enabled, the LCD
operates as a 2 line x 20 character display. New data always displays
on line 2, moving the previous data up to line 1. The following figure
illustrates how the LCD operates when scrolling is disabled (left) and
enabled (right).
Scrolling Disabled (Default)
Message 1 scrolls up to line 1
Message 2 displays on line 2
Message 1 displays on line 2
Message 2 scrolls up to line 1
Message 3 displays on line 2
Scrolling Enabled
BAR CODE DATA 000001
000000 000100
Message 1 displays in positions 1 - 40
1
21
20
40
1 20
40
20
40
1
1
1
20
20
1
1
20
20
20
20
1
1
21
21
Message 2 overwrites message 1
Message 3 overwrites message 2
1 Line x 40 Character Display 2 Line x 20 Character Display
NEW DATA 000002
000000 100000
NO-READ 000003
000001 000000
NEW DATA 000002
NO-READ 000003
BAR CODE DATA 000001
NEW DATA 000002
BAR CODE DATA 000001
Symbols Not Read Counter
Symbols Not Read Counter
Symbols Not Read Counter
Decoder Performance
Package Counter
Package Counter
Package Counter
Decoder Performance
Decoder Performance
You must consider the operating mode of the LCD when displaying
data. If scrolling is disabled, the LCD operates as a l line x 40
character display. Any data that exceeds 40 characters is truncated. If
scrolling is enabled, the LCD operates as a 2 line x 20 character
display. Any data that exceeds 20 characters is truncated.