ETAS
Hardware Description
ES930.1
-
User Guide
23
3.6
Data Transfer
The ES930.1 as well as the ES4xx and ES63x modules use a 100-Mbit/s Ether
-
net network connection in duplex mode for the data transfer. The data transfer
can very flexibly be adapted to the measuring setup and the measuring task.
The universal ASAM measuring and application protocol XCP is used for the
serial communication. On the Ethernet transport and network layer, the UDP/IP
protocol is used (see Fig.
23).
Fig.
3
-
5
Message Format "XCP on UDP" (Schematic)
Within the XCP protocol, the modules also module identification, time stamp
and measuring or stimulation data in a highly precise and predictable time grid.
The communication protocol used for the modules avoids the repeated trans
-
fer of protocol data, as it is the case with handshake-based systems. This pro
-
vides a high bandwidth for the useful data.
The use of the UDP/IP standard for data transfer allows a direct connection of
the modules with a PC, a router or a switch. For the XCP communication, the
PC takes on the master function.
NOTE
The complete Ethernet bandwidth is available for measuring data as well as
output variables.
Changes of output values and variables can be made in a rapid prototyping
application while measuring data are captured at the same time.
SA
48
UDP Header
IFG
min. 96
IP Header
DA
48
Pre
56
SoF
8
CRC
32
Type
16
DATA
n* 8
XCP M essage 1
XCP M essage n
...
XCP on Et hernet M essage
XCP Header
XCP Package
DATA
TIM E STAMP
DAQ
FILL
PID
CTR
LEN
Embedded UDP/IP
Embedded XCP
IEEE802.3 (Et hernet )