Floating point, 4 bcd – Rockwell Automation 2711-ND3 PanelBuilder v2.60 Software User Manual User Manual
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Planning an Application
Publication 2711-6.0
Floating Point
The 32-bit floating point format supports IEEE single precision
formatted values in the range -99,999,997,952 to 999,999,995,904.
The floating point range is limited by the number of display and data
entry character positions available (12) or by the processor. The
PLC-5, SLC 5/03 and SLC 5/04 suppport 7 digits.
The maximum decimal point precision is 9 places for negative values
(-0.000000001) and 10 places for positive values (0.0000000001).
The negative sign occupies 1 character position, values without a
sign are positive. Decimal point values are entered or displayed with
at least one digit to the left of the decimal point.
When large numbers are entered, values to the right of the decimal
may be changed because of the 32-bit floating representation. For
example, if you enter 1.1111111801, PanelBuilder displays
1.1111111641. PanelBuilder uses the closest approximation to
represent your input.
4 BCD
Data in BCD format (also called 4-BCD) occupy one word of
memory. Every four bits encodes a single digit 0
! 9.
Each value occupies one word even if it is less than 9999.
0
0
0
0
0
0
1
0
0
1
1
1
0
1
1
4BCD
(277)
1
2
4
8
1
1
2
4
8
1
2
4
8
1
2
4
8
2
7
7
0