GAMMA
instabus
Release: February 2012
KNX EIB TP-UART 2-IC
Technical Manual
pages 42
Siemens AG
Infrastructure and Cities Sector,
Building Technologies
page 28
© Siemens AG 2012
Control Products and Systems
Subject to change without further notice.
P. O. Box 10 09 53,
D-93009 Regensburg
control field
FFR1 cc00
data link frame type
class
repeat flag
FFR1 0000
L_DATA request
system
set by TP-UART
FFR1 1000
L_DATA request
alarm
set by TP-UART
FFR1 0100
L_DATA request
high
set by TP-UART
FFR1 1100
L_DATA request
normal
set by TP-UART
1111 0000
L_POLLDATA request
system priority
= 1
Fig. 17: Legal EIB-Controlfield
3.2.3.1.9.2
U_L_DataContinue-Service
The U_L_DataContinue-Service transmits one byte of the contents of an EIB-L_Data-Frame to the TP-
UART. The data-index starts with 1 and the maximum value is 62 depending on the length of the
frame.
UART-Controlfield
Additional Information
7
6
5
4
3
2
1
0
7
6
5
4
3
2
1
0
1
0
i
i
i
i
i
i
d
d
d
d
d
d
d
d
L-Data
Data-Index (1 – 62)
EIB-Data Byte for L-Data-Frame
Fig. 18: U_L_DataContinue-Service
3.2.3.1.9.3
U_L_DataEnd-Service
The U_L_DataEnd-Service marks the end of the transmission of the EIB-Frame. After receiving this
service the TP-UART checks the checksum and if correct the transmission starts on the EIB else the
UART returns a state-indication with Receive-Errorflag is set.
UART-Controlfield(80
hex
)
Additional Information
7
6
5
4
3
2
1
0
7
6
5
4
3
2
1
0
0
1
l
l
l
l
l
l
c
c
c
c
c
c
c
c
L-Data
Length (7 – 63)
Checksum
Fig. 19: U_L_DataEnd-Service
3.2.3.1.9.4
U_MxRstCnt
This service adjusts the maximum number of repetitions on bus after a frame has not been
acknowledged with IACK. Values from 0 to 7 are separately adjustable for BUSY or INACK. No
acknowledge will be handled as INACK. If the host clears the repetition flag in the U_L_DataStart
service always no repetitions will be sent.
After Reset 3 repetitions are active.
UART-Controlfield (24
hex
)
MxRstCnt
7
6
5
4
3
2
1
0
7
6
5
4
3
2
1
0
0
0
1
0
0
1
0
0
c
c
c
0
0
c
c
c
Busy Cnt
Nack Cnt
Fig. 20:U_MxRstCnt
3.2.3.1.9.5
U_ActivateCRC
This service activates a 16 bit CRC calculation for every received Layer 2 Service from the bus (except
when the TP-UART is Polling Slave or the busmonitormode is active). However the CRC calculation
only becomes active at the host speed of 19200 Baud.
