Datalogic GWY-01-PBS-01, Справочное руководство

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PROFIBUS INTERFACE
59
5
The Master can see that Bit 0 of the IBCB & IBDCB has been toggled, so it knows that a
new response in the Input Buffer is ready (even though it hasn’t issued a command).
Since
Bit 2 is not set to 1, it knows that the response is complete (not a fragment).
The Master now toggles
Bit 0 of the OBCB & OBDCB to acknowledge that it has received
the response.
(See the
Green changes below)
Output Buffer Input Buffer
Byte # Value Byte # Value
00:
81
Output Buffer Control Byte
(OBCB)
7 6 5 4 3 2 1 0
[1] [0] [0] [0] [0] [0] [0] [1]
00
81 Input Buffer Control Byte
(IBCB)
7 6 5 4 3 2 1 0
[1] [0] [0] [0] [0] [0] [0] [1]
01: 00 (Always 0) 01: 00 (Always 0)
02: 00 (Packet length in bytes) 02: 12 (Packet length in bytes)
03:
04:
05:
06:
07:
08:
09:
10:
11:
12:
13:
14:
15:
16:
17:
18:
19:
20:
..
30: 00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
00
..
00 03:
04:
05:
06:
07:
08:
09:
10:
11:
12:
13:
14:
15:
16:
17:
18:
19:
20:
..
30:
00
09
AA
0D
01
01
01
01
02
12
34
06
11
22
33
44
55
66
..
00 (CBx Response word length MSB)
(CBx Response word length LSB)
Minimum of 6 words
(CBx Response Type)
AA=Normal Response
(CBx Response Opcode)
0D=Continuous Read Response
(CBx Response Instance Counter)
(CBx Response “Node ID”)
(CBx Response Timestamp Month)
(CBx Response Timestamp Day)
(CBx Response Timestamp Hour)
(CBx Response Timestamp Minute)
(CBx Response Timestamp Second)
(CBx Response “Data length”)
6 bytes (the Tag ID)
(CBx Response Data Byte 1)
Tag ID Byte 1
(CBx Response Data Byte 2)
Tag ID Byte 2
(CBx Response Data Byte 3)
Tag ID Byte 3
(CBx Response Data Byte 4)
Tag ID Byte 4
(CBx Response Data Byte 5)
Tag ID Byte 5
(CBx Response Data Byte 6)
Tag ID Byte 6
31: 81 Data Consistency Byte (OBDCB) 31: 81 Data Consistency Byte (IBDCB)
The response has been acknowledged (a read of 6 bytes: 11 22 33 44 55 66).
The reader then reads another tag, puts another response in the Input Buffer, and toggles
Bit 0 again in the IBCB & IBDCB .