Communication
6.6 Communication via USS
Control Units CU240S
180
Operating Instructions, 07/2008 - FW 3.2, A5E00766042B AD
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