Mitsubishi Electronics 13JW55 ユーザーズマニュアル

5 - 55

Project name

QTEST9

Program name

MAIN

5.7.5 Exercise 5 Addition and subtraction instructions

Create a program that:
1) Imports the values specified by the digital switches (X20 to X2F) to D3 and D2

(32-bit data) when X0 is turned on, adds them to D1 and D0, and displays the
result on the displays (Y40 to Y5F).

2) Imports the values specified by the digital switches (X20 to X2F) to D5 and D4

when X1 is turned on, subtracts them from D1 and D0, and displays the result.

3) When the result is a negative number, Y77 is turned on, the two's complement is

determined from the result to obtain the absolute value, and displayed.

Fill in the blanks in the following.
Then, check the operation using the demonstration machine.

PLS

K4X20

DBCD

K8Y40

DBIN

D<=

K4X20

DBIN

DCML

D+P

DBCD

K8Y40

DMOV

Y77

Adds the external
set value to D0.

Displays the result when
it is a positive number.

Subtracts the external
set value from D0.

When the result is a
negative number, it is
converted into a positive
number and displayed.
(The negative absolute
value is determined.)

Outputs that the number
is negative.

Clears D0 and D1.

1)
2)

Reference

DCML

Complement (deny transfer)

The absolute value is determined
by a calculation of two's complement
of D0 and D1 (32-bit data).

B31 B30

B18 B17 B16 B15 B14

B2 B1 B0

Before DCML

execution

(negative number)

After DCML

execution

After D + P execution

(absolute value)

REMARK

The CML instruction inverts the bit pattern of

and transfers the data to

when the input condition is turned on.

Input condition

D10

CML