Statement List (STL) - DCE FEL ČVUT v Praze

3.3 ITB Integer (16-Bit) to BCD
Format
Description
Status word
Example
ITB
Conversion Instructions
ITB (binary to decimal conversion of a 16-bit integer number) interprets the contents
of ACCU 1-L as a 16-bit integer and converts it to a three-digit binary coded decimal
number (BCD). The result is stored in the low word of accumulator 1. Bit 0 to bit 11
contain the value of the BCD number. Bit 12 to bit 15 are set to the state of the sign
(0000 = positive, 1111= negative) of the BCD number. The high word of accumulator
1 and accumulator 2 remain unchanged.
The BCD number can be in the range of "-999" to "+999." If the number is out of the
permissible range, then the status bits OV and OS are set to 1.
The instruction is executed without regard to, and without affecting, the RLO.
BR CC 1 CC 0 OV OS OR STA RLO /FC
writes: - - - x x - - - -
STL Explanation
L MW10 //Load the integer number into ACCU 1-L.
ITB //Convert from integer to BCD (16-bit); store result in ACCU 1-L.
T MW20 //Transfer result (BCD number) to MW20.
ITB
MW10
MW20
15... ...8 7... ...0
1 1 1 1 1 1 1 0 0 1 1 0 0 0 1 1
1
1
1
1
0
1
Integer to BCD
0
0
" - " " 4 " " 1 " " 3 "
0
Statement List (STL) for S7-300 and S7-400 Programming
A5E00706960-01 3-3
0
0
1
0
0
1
1
"-413" Integer
"-413" BCD