96
Allocated CIO Area Words
Section 4-2
4-2-8 Slave Data_Exchange Active Flags (Word n+9 to Word n+16)
The Slave Data_Exchange Active flags indicate for each slave station if it is in
Data_Exchange mode with the PROFIBUS-DP Master Unit. The flags are
allocated to a block of eight CIO words, and each bit in the block corresponds
to a station address.
When a slave station is in Data_Exchange with the PROFIBUS-DP Master
Unit to which it has been allocated, it is exchanging I/O Data with the PROFI-
BUS-DP Master Unit.
If the PROFIBUS-DP Master Unit is in CLEAR mode, it will read the slave’s
input data, but send zeros or an empty message as output data.
If the PROFIBUS-DP Master Unit is in OPERATE mode, it will read the
slave’s input data, and send any output data provided by the PLC CPU
Word n+9 to n+16 [n = CIO 1,500 + (25 x unit number)]]
1514131211109876543210
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Word n+9
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
Word n+10
47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32
Word n+11
63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 48
Word n+12
79 78 77 76 75 74 73 72 71 70 69 68 67 66 65 64
Word n+13
95 94 93 92 91 90 89 88 87 86 85 84 83 82 81 80
Word n+14
111 110 109 108 107 106 105 104 103 102 101 100 99 98 97 96
Word n+15
125 124 123 122 121 120 119 118 117 116 115 114 113 112
Word n+16
Slave station 00 ~ 15
Slave station 16 ~ 31
Slave station 32 ~ 47
Slave station 48 ~ 63
Slave station 64 ~ 79
Slave station 80 ~ 95
Slave station 96 ~ 111
Slave station 112 ~ 125
Bit Name Status Controlled
by
Unit operation
–Slave
Data_Exchange
Active flags
ON Unit If the bit corresponding to a slave station address is ON, it indicates that
this slave station
• is allocated to the PROFIBUS-DP Master Unit, and
• is exchanging I/O Data with PROFIBUS-DP Master Unit.
In this case, the PROFIBUS-DP Master Unit must be in the CLEAR
mode or the OPERATE mode.
OFF Unit If the bit corresponding to a slave station address is OFF, it indicates
that the slave is not in Data_Exchange with this PROFIBUS-DP Master
Unit, due to the fact that
• the slave station is not allocated to this PROFIBUS-DP Master Unit,
or
• the slave station has been allocated to this PROFIBUS-DP Master
Unit, but is forced out of Data_Exchange mode, due to a communica-
tion error, or
• the slave station has been allocated to this PROFIBUS-DP Master
Unit, but is not responding,
• the slave station has been allocated to this PROFIBUS-DP Master
Unit, but is it has temporarily been disabled,
• the PROFIBUS-DP Master Unit is not in CLEAR or OPERATE mode