Mitsubishi Electronics manual 209

11 TROUBLESHOOTING

MELSEC-Q

Special Register List

(10) Special register list dedicated for QnA

ACPU

Special

Special

Corresponding

Special

Register after

Register for

Name

Meaning

Details

CPU

Conversion

Conversion

Modification

Stores the execution result of the ZNRD (word device

0: Normal end

read) instruction

ZNRD

2: ZNRD instruction

• ZNRD instruction setting fault:

Faulty setting of the

setting fault

ZNRD instruction

(LRDP for

3: Error at relevant

constant, source,

D9200

SD1200

ACPU)

station

and/or destination

processing

4: Relevant station

• Corresponding station error:

One of the stations is

results

ZNRD execution

not communicating.

disabled

• ZNRD cannot be executed in

The specified station is

the corresponding station:

a remote I/O station.

0: Normal end

Stores the execution result of the ZNWR (word device

write) instruction.

2: ZNWR

• LWTP instruction setting fault:

Faulty setting of the

ZNWR

instruction setting

(LWTP for

fault

ZNWR instruction

constant, source,

D9201

SD1201

ACPU)

3: Error at relevant

and/or destination.

processing

station

• Corresponding station error:

One of the stations is

results

4: Relevant station

ZNWR execution

not communicating.

disabled

• ZNWR cannot be executed in

The specified station is

QnA

the corresponding station:

a remote I/O station.

Stores whether the slave station corresponds to

MELSECNET or MELSECNET II.

• Bits corresponding to the MELSECNET II stations

Stores conditions

become "1."

D9202

SD1202

for up to numbers 1

• Bits corresponding to the MELSECNET stations or

to 16

unconnected become "0."

Device

Bit

number

b15

b14

b13

b12

b11

b10

b9

b8

b7

b6

b5

b4

b3

b2

b1

b0

SD1202

L16

L15

L14

L13

L12

L11

L10

L9

L8

L7

L6

L5

L4

L3

L2

L1

Local station link

SD1203

L32

L31

L30

L29

L28

L27

L26

L25

L24

L23

L22

L21

L20

L19

L18

L17

SD1241

L48

L47

L46

L45

L44

L43

L42

L41

L40

L39

L38

L37

L36

L35

L34

L33

type

SD1242

L64

L63

L62

L61

L60

L59

L58

L57

L56

L55

L54

L53

L52

L51

L50

L49

• If a local station goes down during the operation, the

Stores conditions

contents before going down are retained.

Contents of SD1224 to SD1227 and SD1228 to

D9203

SD1203

for up to numbers

SD1231 are ORed. If the corresponding bit is "0", the

17 to 32

corresponding bit of the special register above

becomes valid.

• If the own (master) station goes down, the contents

before going down are also retained.

0: Forward loop,

during data link

Stores the present path status of the data link.

1: Reverse loop,

• Data link in forward loop

during data link

Master

2: Loopback

station

Station 1

Station 2

Station n

implemented in

forward/reverse

directions

D9204

SD1204

Link status

3: Loopback

Forward loop

Reverse loop

QnA

implemented

• Data link in reverse loop

only in forward

Master

direction

station

Station 1

Station 2

Station n

4: Loopback

implemented

only inreverse

direction

5: Data link

Forward loop Reverse loop

disabled

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