Omron C200H - Bcd Subtract - Sub(31)

166
Flags ER: Au and/or Ad is not BCD.
Indirectly addressed DM word is non-existent. (Content of *DM word
is not BCD, or the DM area boundary has been exceeded.)
CY: ON when there is a carry in the result.
EQ: ON when the result is 0.
When 00000 is ON, the following program adds two 12-digit numbers, the
first contained in LR 20 through LR 22 and the second in DM 0012. The re-
sult is placed in LR 10 through HR 13. In the second addition (using
ADD(30)), any carry from the first addition is included. The carry from the
second addition is placed in HR 13 by using @ADB(50) (see Section 5-18-1)
with two all-zero constants to indirectly place the content of CY into HR 13.
@ADDL(54)
LR 20
DM 0010
HR 10
CLC(41)
00000
@ADD(30)
LR 22
DM 0012
HR 12
@ADB(50)
#0000
#0000
HR 13
Address Instruction Operands
00000 LD 00000
00001 CLC(41)
00002 @ADDL(54)
LR 20
DM 0010
HR 10
00003 @ADD(30)
LR 22
DM 0012
HR 12
00004 @ADB(50)
# 0000
# 0000
HR 13
5-17-7 BCD SUBTRACT – SUB(31)
Mi: Minuend word (BCD)
IR, SR, AR, DM, HR, TC, LR, #
Su: Subtrahend word (BCD)
IR, SR, AR, DM, HR, TC, LR, #
Ladder Symbols
Operand Data Areas
R: Result word
IR, AR, DM, HR, LR
SUB(31)
Mi
Su
R
@SUB(31)
Mi
Su
R
When the execution condition is OFF, SUB(31) is not executed. When the
execution condition is ON, SUB(31) subtracts the contents of Su and CY
from Mi, and places the result in R. If the result is negative, CY is set and the
10’s complement of the actual result is placed in R. To convert the 10’s com-
plement to the true result, subtract the content of R from zero (see example
below).
Mi – Su – CY CY R
Example
Description
BCD Calculations Section 5-17