Rockwell Automation 2706-MB1 MESSAGEVIEW 421 SOFTWARE MANUAL - Manual (Page 81)

4–33 Planning an Application
Publication 2706-817
The MessageView terminal can read and write both of these data
types:
•
single bit data type
•
value data type.
Bit data
Bit data occupies a single bit address and represent an On (closed) or
Off (open) condition.
Address B3/10 = On = Off 1 0
Use a bit address:
•
to read or write a value of 0 or 1 in a variable
•
to trigger a message.
Value data
Value data types occupy a word (2 bytes or 16 bits) address that
represents a numeric value. No matter how large or small the value, a
whole word must be assigned to it.
0 0 0 0 0 0 0 1 0 0 0 1 0 1 0
1 2 4 8 16 32 64 128 256 512 1024 2048 4096 8192 16384 32768
1
Address N7:2
= 277
Data Formats
The MessageView terminal recognizes and transfers 5 data formats.
Data Format Range
Bit 0 or 1
Unsigned Integer 0 to 65535
Signed Integer -32768 to +32767
BCD 0 to 9999
Character Array alphanumeric characters
Bit
Data in bit format occupies only one bit of memory. Its address is
given not as a word (N7:2), but as a bit (N7:2/10). A bit is a location,
and depends on its position in the word. It can be set or reset.
Data Types