Operating instructions
Communication
6.6 Communication via USS
Control Units CU240S
Operating Instructions, 10/2007, A5E00766042B AC
183
6.6.4 Use data area of USS telegram
Basic USS parameters
General rule: Index[0] for USS on RS485, Index[1] for USS on RS232.
P2010 USS Baudrate [2400 … 115200] baud
P2011 USS Slave Address: [0 … 30]
P2012 USS PZD Length: [0 … 2 … 8] words
P2013 USS parameter channel length: [0, 3 (3 words), 4 (4 words), 127 (variable
length)]
P2014 USS Telegram Off-Time: [0 … 65535] ms. ‘0’ = no timeout check!
R2015 Received PZD via USS on RS232
P2016 BICO Selection for PZDs to be sent via USS on RS232
R2018 Received PZD via USS on RS485
P2019 BICO Selection for PZDs to be sent via USS on RS485
r2032 Control Word 1 from USS on RS232
r2033 Control Word 2 from USS on RS232
r2036 Control Word 1 from USS on RS485
r2037 Control Word 2 from USS on RS485
Use data structure
The use data area of the USS protocol is used for transferring the application data, which are
the parameter channel and process data (PZD).
The application data occupies the bytes within the USS frame (STX, LGE, ADR, BCC). The
size of the application data can be configured by parameters p2013 and p2012. The
following figure shows the structure and order for the parameter channel and process data
(PZD).
3.( ,1' 3:( 3:( 3:(P
3
3
3
3
3
Q
3.: 3.: 3.: 3.: 3.:P 3=' 3=' 3='\
67:
=6:
+6:
+,:
3
3
3='
3
3
3='
67:
=6:
3 3
3
3
3
3 YDULDEOHOHQJWK
3URFHVVGDWD3='
3.:3='VWUXFWXUH
'DWD%\WHV
3URWRFRO'DWD
3DUDPHWHUFKDQQHO3.:
3URWRFRO:RUGV
Figure 6-17 USS use data structure