Omron SYSMAC CJ - REFERENCE MANUAL 08-2008 Reference Manual page 561

Conversion Instructions
Description
Area
Index Registers
Indirect addressing
using Index Registers
BISL(472) converts the double signed BCD data in S+1 and S to double
signed binary data and writes the result in D+1 and D. First the signed BCD
data format and range in words S+1 and S are checked against the setting in
the control word (C). If the source data is correct, the signed BCD data S+1
and S is converted to signed binary and output to D+1 and D. If the source
data is incorrect, the Error Flag will be turned ON and the instruction will not
be executed.
When the converted data is negative, it will be output as the 2's complement
and the Negative Flag be will turned ON. NEGL(161) can be used to deter-
mine the absolute value of a negative double signed binary number. Refer to
3-12-6 DOUBLE 2'S COMPLEMENT: NEGL(161) for details.
Values of –0 in the source data will be treated as 0 and will not cause an error.
Also, the status of bits 13 to 15 of S+1 is not checked when C=0000.
Note Some Special I/O Units output signed BCD data. Calculations using this data
will normally be easier if it is first converted to signed binary data with
BISL(472).
The control word specifies the signed BCD format as shown below.
C = 0000 (Input Data Range: –999 9999 to 999 9999 BCD)
S+1
C = 0001 (Input Data Range: –7999 9999 to 7999 9999 BCD)
S+1
C
---
,IR0 to ,IR15
–2048 to +2047 ,IR0 to –2048 to +2047 ,IR15
DR0 to DR15, IR0 to IR15
,IR0+(++) to ,IR15+(++)
,–(– –)IR0 to, –(– –)IR15
Signed BCD format
specified in C
Signed binary
Signed BCD
Signed BCD
Signed binary
S
7 digits BCD, 28 bits
Sign bit (0: Positive; 1: Negative)
Status of 3 bits: 0
S
7 digits BCD, 28 bits
3 bits of digit 8 (0 to 7)
Sign bit (0: Positive; 1: Negative)
Section 3-12
S D
521