Siemens SINEC L2 User Manual

Data Transmission by Accessing Layer 2 Services S5-95U, SINEC L2
Figure 8-4. Request, Confirmation and Indication Structures
Request
com_class
FDL_Request=00
H
(request for layer 2 service)
Byte
a a a a a
a
a a a
a
a a a a a
0
Confirmation
com_class
FDL_Confirmation=01
H
(Confirmation from layer 2
firmware following request)
Byte
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
1 user_id
ID assigned in connection with
a request
service_code
Type of service provided
a a a a a
a
a a a
a
a
a a a
a
a a a a a
2
link_status
OK or error message; indicates
success or failure of preceding
request
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
1
service_code
Type of service requested
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
Indication
com_class
Indication=02
H
(indication that data have been
received)
Byte
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
1
irrelevant
service_code
Type of service provided
a a a a a
a
a a a
a
a
a a a
a
a a a a a
2
irrelevant
a a a a a
a
a a a
a
a
a a a
a
a a a a a
3
user_id
User-definable ID
(echoed in a confirmation)
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 (hexadecimal)
a a a a a
a
a a a
a
a
a a a
a
a a a a a
5 SAP No. of the receiver =
destination SAP
(hexadecimal)
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
a a a a a
7 rem_add_segment
Logical segment address;
always enter FF
H
(no other segments can be
currently addressed)
Bits 4 to 7
service_class
Priority of
send frame
Send 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
a a a a a
8
.
.
.
249
a a a a a
a
a a a
a
a
a a a
a
a a a a a
4
SAP No. of the receiver =
destination SAP
(hexadecimal)
rem_add_station
Address of the destination
station (hexadecimal)
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
a a a a a
7
Bits 0 to 3
0
Bits 4 to 7
service_class
Priority of the
send message
a a a a a
a
a a a
a
a
a a a
a
a a a a a
4
SAP No. of the sender =
source SAP
(hexadecimal)
rem_add_station
Address of source station
(hexadecimal)
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
a a a a a
7
Bits 0 to 3
0
Bits 4 to
service_class
Priority of
receive frame
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
a a a a a
8
.
.
.
249
Receive data in connection with
SRD service (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
a a a a a
8
.
.
.
249
rem_add_segment
Logical segment address;
is always FF
H
(no other segments can be
currently addressed)
rem_add_segment
Logical segment address;
is always FF
H
(no other segments can be
currently addressed)
You can store the requests and indications (up to 250 bytes each) in the flag area or data area.
In view of the relatively large maximum amount of data, however, we advise you to use only the
data area.
Section 8.5 describes the structure of requests, confirmations and indications for the special layer 2
services.
As a prerequisite for using layer 2 services, you must first
• specify an SAP number in DB1 ( section 8.3)
• define two status bytes in DB1 ( section 8.3)
• assign L2-SEND and L2-RECEIVE their parameters ( section 8.3, chapter 5)
• create DBs for the request, the confirmation and the indication ( from section 8.5 ff.).
8-8 EWA 4NEB 812 6112-02

Siemens SINEC L2 Specifications

General

Brand	Siemens
Model	SINEC L2
Category	Controller
Language	English