Siemens SINEC L2 User Manual

Data Transmission by Accessing Layer 2 Services S5-95U, SINEC L2
Requesting Data (SRD Layer 2 Service without Send Data)
If you do not want your sender to send any data to the receiver, but only request data from the
receiver, use the special case of the "SRD without send data" layer 2 service.
Prerequisite for data transmission:
You must hold data requested by the sender ready for fetching with the RUP_SINGLE
( section 8.7) or RUP_MULTIPLE layer 2 service ( section 8.8).
Fetching the data by the sender ( Figure 8-14):
The request (header + net data to be transmitted) in the flag or data area is sent with L2-SEND
(request to layer 2).
The 'Receive" status byte informs the receiver that an indication has arrived.
The receiver fetches the indication (header) with L2-RECEIVE.
The 'Send' status byte informs the sender that a confirmation has been transmitted.
The sender fetches the confirmation (= header + net data requested by the receiver) with L2-
RECEIVE.
Figure 8-15 shows the request confirmation and indication structures for the SRD service
Figure 8-15. Structure of Requests, Confirmations and Indications for the SRD Service
Destination SAP 0 to 62,
FF (=default SAP 64)
Request
com_class
FDL_Request=00
H
Byte
a a a a a
a
a a a
a
a
a a a
a
a a a a a
0
Confirmation
com_class
Confirmation=01
H
Byte
a a a a a
a
a a a
a
a
a a a
a
a a a a a
0
a a a a a
a
a a a
a
a
a a a
a
a a a a a
1 user_id
ID assigned in connection with
a request
a a a a a
a
a a a
a
a
a a a
a
a a a a a
1
Indication
com_class
Indication=02
H
Byte
a a a a
a
a a
a
a
a a
a
a a a a
0
a a a a
a
a a
a
a
a a
a
a a a a
1
irrelevant
user_id
User-definable ID
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a a a a a
a
a a a
a
a
a a a
a
a
a a a
a
a
a a a
a
a
a a a
a
a
a a a
a
a a a a a
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a a a a a
a
a a a
a
a
a a a
a
a a a a a
4 Bits 0 to 3
0
rem_add_station
Address of the destination
station (1 to 126)
a a a a a
a
a a a
a
a
a a a
a
a a a a a
5
a a a a a
a
a a a
a
a
a a a
a
a a a a a
6
a a a a a
a
a a a
a
a a a a a
7 rem_add_segment
Logical segment address;
always enter FF
H
Bits 4 to 7
service_class
Priority of
send message
low=0
H
or
high=1
H
Send data
(0 to 242 bytes)
service_code
Type of service:
SRD=03
H
a a a a a
a
a a a
a
a
a a a
a
a a a a a
2
link_status
( Table 8-9 )
a a a a a
a
a a a
a
a
a a a
a
a a a a a
3
a a a a a
a
a a a
a
a
a a a
a
a a a a a
4
Destination SAP 0 to 62,
FF (=default SAP 64)
rem_add_station
Address of the destination
station (1 to 126)
a a a a a
a
a a a
a
a
a a a
a
a a a a a
5
a a a a a
a
a a a
a
a
a a a
a
a a a a a
6
a a a a a
a
a a a
a
a a a a a
7 rem_add_segment
Logical segment address;
is always FF
H
Bits 0 to 3
0
Bits 4 to 7
service_class
Priority of the
send message
low=0
H
or
high=1
H
service_code
Type of service requested:
SRD=03
H
a a a a a
a
a a a
a
a
a a a
a
a a a a a
2
a a a a a
a
a a a
a
a
a a a
a
a a a a a
3
irrelevant
service_code
Type of service:
SRD=03
H
a a a a
a
a a
a
a
a a
a
a a a a
2
link_status
( Table 8-10 )
a a a a
a
a a
a
a
a a
a
a a a a
3
a a a a
a
a a
a
a
a a
a
a a a a
4
Source SAP 0 to 62,
FF (=default SAP 64)
rem_add_station
Address of source station
(1 to 126)
a a a a
a
a a
a
a
a a
a
a a a a
5
a a a a
a
a a
a
a
a a
a
a a a a
6
a a a a
a
a a
a
a a a a
7 rem_add_segment
Logical segment address;
is always FF
H
Bits 0 to 3
0
Bits 4 to 7
service_class
Priority of
receive
message
low=0
H
or
high=1
H
Receive data
(0 to 242 bytes)
a a a a a
a
a a a
a
a
a a a
a
a
a a a
a
a
a a a
a
a
a a a
a
a
a a a
a
a a a a a
8
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a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a a a a a
a
a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a
a
a a a a a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a a a a a a a a a
a
a a a a a a a
a
a
a a a a a a a
a
a a a a a a a a a
Must be specified by the user in the request header
Data held ready by the
receiver for fetching
(0 to 242 bytes)
a a a a a
a
a a a
a
a
a a a
a
a
a a a
a
a
a a a
a
a
a a a
a
a
a a a
a
a a a a a
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8-30 EWA 4NEB 812 6112-02

Siemens SINEC L2 Specifications

General

Brand	Siemens
Model	SINEC L2
Category	Controller
Language	English