Rockwell Automation 1771-DB BASIC MODULE - Manual (Page 106)

Chapter
Data Types 8
8 -6
4-Digit, Unsigned, Fixed Decimal BCD
This value requires one word of the processor data table. The data is
represented by a 4-digit BCD integer. The value ranges from 0–9999.
There is no indication of sign, underflow or overflow. However, if a value
of greater than 9999 is converted or an invalid number, the value reported
is 0000. Fractional portions of any number used with the routine are
truncated. See CALL 17 (page 12 -11) and CALL 27 (page 12 -17).
17 16 15 14 13 12 11 10 07 06 05 04 03 02 01 00
BCD Value
implied
decimal point
15033
D4 D3 D2 D1
4-Digit, Signed, Octal
This value requires one word of the processor data table. The data is
represented by a 4-digit octal integer. The value ranges from +7777
8
(+4095). Overflow, underflow and sign are also indicated. If an overflow
or underflow condition exists, the appropriate bit is set and the value of
000 is reported. Fractional portions of any number used in this routine are
truncated. See CALL 12 (page 12 -7) and CALL 22 (page 12 -13).
17 16 15 14 13 12 11 10 07 06 05 04 03 02 01 00
not used
underflow bit (1 = value is fractional and between +1 & –1
(ie. +.999 to –.999)
sign bit (1 = negative; 0 = positive)
overflow bit (1 = value > +999)
Octal Value
implied
decimal point
15034
D3 D2 D1 D4
–