16
Addressing/terminating
Instruction book, IQAN- MC31
Addressing/terminating
IQAN-MC31 use of an ID-Tag
In IQANdesign 3.0 and higher software, more than one IQAN master module can be
used together in a multi-master system. The master modules are each given a unique
address by using an ID-Tag. The value of the ID-Tag identifies the master and will
enable a single project application to be loaded into more than one master module over
the CAN bus. The functionality needed for each master is loaded based on the ID-tag
address.
Identification of an IQAN-MC31 by address
For normal operation of an IQAN-MC31 in a single master system, the ID-Tag is still
used. When no ID-Tag is installed the MC31 or if the ADDR pins are jumpered on
power up, the MC31 will start in safe mode.
The connection of an ID-Tag between ADDR-H and ADDR-L will assign an address to
the IQAN-MC31 master module. The desired functionality based on address is built
into the project file using IQANdesign software. For more information, please refer to
the IQANdesign user manual.
It is the combination of
address
and
type
that gives each master module a unique
identification. The maximum number of MC31 addresses is 8, denoted as addresses 0,
1, 2, 3, 4, 5, 6, 7 respectively.
In order to assign any IQAN-MC31 an address , an
ID-Tag
will have to be connected to
the positions ADDR-H and ADDR-L.
Connecting of Id-Tag.
Terminating
To eliminate interference in the communications through the CAN bus, the CAN bus
must be terminated. By default, the MC31 is terminated internally on all of its CAN
buses. When an IQANdesign application is loaded, it can set individual buses to be
non-terminated.
To give an IQAN-MC31 a unique address, you may use an addressing ID-tag, or an ID-
tag having a combined address and terminating function. The ’T’ values of ID-tags are
ignored, i.e. an ID-tag 3T is equivalent to ID-tag 3.
If the module is located at the end of the CAN-bus, then leave the bus default
terminated in the MC31.
N
OTICE
The CAN-bus should not be terminated at the MC31 using an external regular
terminating resistor, due to the fact that terminating is made from within the MC31
module by default.
ID-Tag
ADDR-L
ADDR-H
IQAN-MC31
