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GAMMA
instabus
Release: February 2012
KNX EIB TP-UART 2-IC
Siemens AG
pages 42
Technical Manual
Infrastructure and Cities Sector,
Building Technologies
Control Products and Systems
© Siemens AG 2012
page 29
P. O. Box 10 09 53,
Subject to change without further notice.
D-93009 Regensburg
The TP-UART calculates over the complete received telegram (including the Layer 2 checksum) a
CRC16-CCITT with the following parameters:
-
Width= 16 bit
-
Truncated polynomial = 1021hex
-
init value = FFFFh
-
I/O not reflected
-
no xor on output CRC
-
Test string „123456789“ is 0xE5CC
and adds it to the receiving frame (sending order is highbyte then lowbyte).
After Reset CRC calculation is disabled.
UART-Controlfield (25
hex
)
7
6
5
4
3
2
1
0
0
0
1
0
0
1
0
1
Fig. 21: U_ActivateCRC
3.2.3.1.9.6
U_PollingState
This service must be send to the TP-UART if an Pollingframe-Ctrlbyte is received. If the TP-UART
detects a collision during sending the slave slot to the EIB the TP-UART generates a State indication
with the Slave Collisionflag set.
UART-Controlfield
Polling Address high
7
6
5
4
3
2
1
0
7
6
5
4
3
2
1
0
1
1
1
0
s
s
s
s
c
c
c
c
c
c
c
c
Slotnumber
Polling Address low
Pollingstate
7
6
5
4
3
2
1
0
7
6
5
4
3
2
1
0
c
c
c
c
c
c
c
c
c
c
c
c
c
c
c
c
Fig. 22: U_PollingState-Service
Ctrl-Byte
Src-Addr
Src-Addr
PollAddr
PollAddr
Receive from Bus
s 0 1 2 3 4 5 6 7 p s
s 0 1 2 3 4 5 6 7 p s
s 0 1 2 3 4 5 6 7 p s
s 0 1 2 3 4 5 6 7 p s
s 0 1 2 3 4 5 6 7 p s
Ctrl-Byte
Send to Controller
s 0 1 2 3 4 5 6 7 p s
PSlotnr
PollAddr
PollAddr
Rec from Controller
s 0 1 2 3 4 5 6 7 p s
s 0 1 2 3 4 5 6 7 p s
s 0 1 2 3 4 5 6 7 p s
s
Send to Bus