Hitachi HIDIC MICRO-EH Applications Manual Download

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Chapter 5 Instruction Specifications

5-108

Syntax of FOR to NEXT

FOR 1 (WR0010)

NEXT 2

NEXT 5

FOR 5 (WM04F)

Program

NEXT 3

FOR 3

Program

FOR 3 (WR10)

NEXT 3

SB1

NEXT 2

FOR 3(WR0003)

RTS

SB2

NEXT 3

FOR 4(WR0004)

RTS

INT0

NEXT 4

NEXT 1

RT1

FOR 1(WR0001)

FOR 2(WR0002)

END

FOR3

Program

FOR 1 (WM001)

NEXT 1

Program

FOR 2 (WM002)

NEXT 2

FOR 1 (WM001)

CJMP 10 (X00000)

NEXT 1

LBL10

FOR 1(WR0001)
FOR 2(WR0002)
FOR 3(WR0003)
FOR 4(WR0004)
FOR 5(WR0005)
FOR 6(WR0006)

NEXT 6
NEXT 5
NEXT 4
NEXT 3
NEXT 2
NEXT 1

X00000

JMP 1

FOR 1(WM001)

NEXT 1

LBL 1

Program C

WR0010=1

WR0010=20

FOR 1(WR0010)

Program A

NEXT1

R005

Program B

FOR 1(WM001) to NEXT 1 will execute
normally.

•

Nesting error
When WM002=0

Since FOR 1(WM001) to NEXT 1 is
prioritized, jump will not be performed
over NEXT 1 from FOR 2 to NEXT 2.
At this time, NEXT 2 generates a FOR
2 undefined error.

When WM002

≠

FOR 2 will not do anything. Therefore,
NEXT 2 will generate a FOR 2
undefined error.

•

When R005 is off
Program B is executed after program A is repeated 20
times.

•

When R005 is on
The repeat counter WR0010 changes to 1, and since the
NEXT 1 processing subtracts 1 from it, the content of
WR0010 becomes 0. Therefore, the repeating of
program A is terminated and program B is execute

4] Use FOR to NEXT as a nest.

8] The number of repeats may be modified within the

program.

The content of WR0010
decrements by 1 and a jump is
performed to FOR 1 (WR0010).

1] A NEXT instruction with the same code number as the

code number n of the FOR instruction is required after
the FOR instruction.

5] It is possible to escape from a FOR to NEXT loop

using a jump instruction.

•

NEXT undefined error
The NEXT instruction with
respect to the FOR instruction
does not exist within the user
program.

•

FOR undefined error
The FOR instruction does not exist
before the NEXT instruction.

•

NEXT to FOR error
The NEXT instruction exists
before the FOR instruction.

The FOR 1 to NEXT 1 loop is
escaped when X00000 turns on
before the loop has been repeated
for the set number of repeats
(content of WM001).

2] An overlap of FOR and NEXT instructions with the

same code number n is not allowed.

6] FOR to NEXT may be nested up to 5 levels. When a

subroutine is included, the FOR to NEXT within the
subroutine is counted.

•

Nesting overflow error

•

FOR duplicate-definition error
A FOR instruction with the same
code number n is programmed.

•

NEXT duplicate-definition error
A NEXT instruction with the same
code number n is programmed.

Note: FOR and NEXT duplicate-

definition errors will occur
during operation pre-processing.

3] FOR and NEXT must be within the same area.

7] Do not include a startup condition between FOR and

NEXT. If a startup condition is required, create a
circuit as shown below:

Program head

Normal scan

Subroutine
SB1

Subroutine
SB2

Interrupt scan

[Operation description]

When X00000 is off, program C is
repeatedly executed for the
number of WM 1 times.
When X00000 is on, program C is
not executed since a jump is
performed from JMP 1 to LBL 1.

NE
X