ETAS ES595.1, Руководство пользователя

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ETAS Functional Description
ES595.1 - User Guide 24
5.7 CAN Interface (CAN1/LIN1, CAN2/LIN2)
The ES595.1 has two CAN interfaces. One each of the CAN interfaces is routed
to the two 8-pin CAN1/LIN1 and CAN2/LIN2 connectors (Lemo socket) on the
front panel.
CAN1 and CAN2 are complete independent CAN channels with separated con
-
nections and CAN controllers. The CAN interfaces produce a simple and direct
connection between the ES595.1 and the CAN network.
The interfaces are galvanically isolated from each other and from the other
interfaces of the ES595.1.
5.7.1 Operating Modes
The CAN interfaces of the ES595.1 can be operated in High-Speed CAN link
(ISO 11898-2) or Low-Speed CAN link (ISO 11898-3). Switching between the
two operating modes is controlled by software. The operating mode can be
selected individually for each interface.
5.7.2 Feature
You can find a list of CAN applications supported by the ES595.1 in chapter
8.8.2 on
page 49.
5.7.3 Bus Terminating Resistor
Low-Speed CAN
In the ES595.1, two relatively high-impedance termination resistors of 2.26
kOhm each (RTH, RTL) are integrated for the Low-Speed CAN link.
This guarantees that, in a terminated CAN network, the ES595.1 does not have
a great influence on the sum of the terminations of the overall system. This
should, however, be checked regardless particularly with lab networks or with
tests in existing networks.
In a Low-Speed CAN network, the individual nodes are typically terminated with
500
Ohm to 6 kOhm. To ensure optimum system conditions, the CAN network
should be terminated with around 100 Ohm (parallel connection of all termina -
tions).
For more details on the Low-Speed CAN network, consult the ISO/DIS 11898
“Road vehicles — Controller area network (CAN) — Part 3: Low-Speed, fault-tol
-
erant, medium dependent interface”.
NOTE
The four interfaces CAN1 and LIN1 (CAN1/LIN1 connector) or CAN2 and
LIN2 (CAN2/LIN2 connector) can be configured and used simultaneously
and independently of one another.
NOTE
The bus termination resistors intended for High-Speed CAN can not be used
in this operating mode!