Rockwell Automation 1771-DB Basic Module User Manual - Series A - Manual (Page 146)

Data Types
Chapter 7
7–4
This value requires two words of the processor data table. The first word
contains overflow, underflow and sign data and the three most significant
digits of the 6-digit BCD integer. The second word contains the lower three
digits of the value (figure 7.5). The value ranges from -999999 to +99999.
If an overflow or underflow condition exists, the appropriate bit is set and
a value of 000000 is reported. Fractional portions of any number used with
this routine are truncated.
Figure 7.5
Truncated 6-Digit BCD Integer
7.2.5
6-digit, Signed,
Fixed Decimal BCD