APPENDICES
Appendix 2 Special Register List
App
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9
P
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Device
Exp
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11
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In
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ACPU
Special
Register
Special
Register
after
Conversion
Special
Register for
Modification
Name
Meaning
Details
Corresponding
CPU
D9204
SD1204
–
Link status
0 : Forward loop,
during data link
1 : Reverse loop,
during data link
2 : Loopback
implemented in
forward/reverse
directions
3 : Loopback
implemented only
in forward
direction
4 : Loopback
implemented only
in reverse
direction
5 : Data link disabled
• Loopback in forward loop only
• Loopback in reverse loop only
QnA
D9205
SD1205
–
Station
implementing
loopback
Station that
implemented forward
loopback
Stores the local or remote I/O station number at which loopback is
being executed.
In the above example, 1 is stored into D9205 and 3 into D9206.
If data link returns to normal status (data link in forward loop), values
in D9205 and D9206 remain 1 and 3. To return them to "0", therefore,
use a sequence program or perform reset operation.
D9206
SD1206
–
Station
implementing
loopback
Station that
implemented reverse
loopback
D9210
SD1210
–
Number of
retries
Stored as cumulative
value
Stores the number of retry times due to transmission error.
Count stops at maximum of "FFFF
H
" .
To return the value to "0", perform reset operation.
D9211
SD1211
–
Number of
times loop
selected
Stored as cumulative
value
Stores the number of times the loop line has been switched to reverse
loop or loopback.
Count stops at maximum of "FFFF
H
".
To return the value to "0", perform reset operation.
D9212
SD1212
–
Local station
operation status
Stores conditions for
up to numbers 1 to 16
Stores the local station numbers which are in STOP or PAUSE mode.
When a local station is switched to STOP or PAUSE mode, the bit
corresponding to the station number in the register becomes "1".
Example: When station 7 switches to STOP mode, b6 in SD1212
becomes "1" , and when SD1212 is monitored, its value is
"64 (40
H
)".
D9213
SD1213
–
Local station
operation status
Stores conditions for
up to numbers 17 to
32
D9214
SD1214
–
Local station
operation status
Stores conditions for
up to numbers 33 to
48
D9215
SD1215
–
Local station
operation status
Stores conditions for
up to numbers 49 to
64
D9216
SD1216
–
Local station
error detect
status
Stores conditions for
up to numbers 1 to 16
Stores the local station numbers which are in error.
If a local station detects an error, the bit corresponding to the station
number becomes "1".
Example: When station 6 and 12 detect an error, b5 and 11 in
SD1216 become "1", and when SD1216 is monitored, its
value is "2080 (820
H
)".
D9217
SD1217
–
Local station
error detect
status
Stores conditions for
up to numbers 17 to
32
D9218
SD1218
–
Local station
error detect
status
Stores conditions for
up to numbers 33 to
48
D9219
SD1219
–
Local station
error detect
status
Stores conditions for
up to numbers 49 to
64
Forward loopback
Station
No. n
Station
No.2
Station
No.3
Station
No.1
Master
station
Reverse loopback
Station
No. n
Station
No.2
Station
No.3
Station
No.1
Master
station
Forward loopback
Reverse loopback
Station
No. n
Station
No.2
Station
No.3
Station
No.1
Master
station
SD1212
SD1213
SD1214
SD1215
Bit
L16 L15 L14 L13 L12 L11
L32 L31 L30 L29 L28 L27
L48 L47 L46 L45 L44 L43
L64 L63 L62 L61 L60 L59
L26
L42
L58
L25
L41
L57
L24
L40
L56
L23
L39
L55
L22
L38
L54
L21
L37
L53
L20
L36
L52
L19
L35
L51
L18
L34
L50
L17
L33
L49
L10 L9 L8 L7 L6 L5 L4 L3 L2 L1
b15 b14 b13 b12 b11 b10 b9 b8 b7 b6 b5 b4 b3 b2 b1 b0
Device
number
SD1216
SD1217
SD1218
SD1219
Bit
L16 L15 L14 L13 L12 L11
L32 L31 L30 L29 L28 L27
L48 L47 L46 L45 L44 L43
L64 L63 L62 L61 L60 L59
L26
L42
L58
L25
L41
L57
L24
L40
L56
L23
L39
L55
L22
L38
L54
L21
L37
L53
L20
L36
L52
L19
L35
L51
L18
L34
L50
L17
L33
L49
L10 L9 L8 L7 L6 L5 L4 L3 L2 L1
b15 b14 b13 b12 b11 b10 b9 b8 b7 b6 b5 b4 b3 b2 b1 b0
Device
number