Siemens SIMATIC S5 CP 523 Manual page 240

CP 523
A.6 Feedback Information in Communications Modes 1 and 2
Table A-12. Coordination Information for "Coordinate Data Transfer" (CP to CPU) ( 7.4)
Byte
0 Status byte
1 Permission to send and receive
2+3 Message frame length in bytes*
4+5 Not significant
6 Number of message blocks of the next message frame in the
Receive mailbox
7 Number of message frames in the Receive mailbox
* Only after "Receive message frames" request A080
Table A-13. Status Information and Current Clock Data (CP to CPU)
Byte
0 Status byte
1 Status of the peripheral device
Bits 4 to 7:
Bits 0 to 3:
1=Sunday, 2=Monday, 3=Tuesday, 4=Wednesday
5=Thursday, 6=Friday, 7=Saturday
2 Current day
3 Current month
4
Current year
5
Current hour
6 Current minute
7
Current second
EWA 4NEB 811 6044-02a
Meaning
CPU can neither send nor receive
CPU can send
CPU can receive
CPU can send and receive
H
Meaning
Peripheral device ready
Peripheral device not ready
Current day of the week
12h clock a.m.
12h clock p.m.
Possible Values
0000 to 0100
H
00
00
*
Possible Values
X1
BCD
01
BCD
01
BCD
00
BCD
24 h clock 00
BCD
01
BCD
81
BCD
00
BCD
00
BCD
Summary
5X
H
00
H
01
H
80
H
81
H
H
0000
H
to 20
H H
to 64
H H
7.4
0X
BCD
1X
BCD
to X7
BCD
to 31
BCD
to 12
BCD
to 99
BCD
to 23
BCD
to 12
BCD
to 92
BCD
to 59
BCD
to 59
BCD
A-11