Data Interface CANopen®
English, Revision 06, Date: 12.07.2011
38
5
Data Interface CANopen®
The Node ID and the transmission rate have to be selected either according to the
above described serial monitor or the corresponding SDOs. The measured values of
the system are transmitted via a so-called TxPDO. SDOs are used for parameter set-
ting. The CAN Identifier are determined from the Node address (1..127).
The parallel input should be deactivated, in order to enable control (enable, turn, etc.)
via the CAN bus. The deactivation is either generated in submenu
(O)utput-Input
Settings
(refer to section 4.4 on page 26) or via RxPDO by deleting the correspond-
ing configuration bit.
5.1
Description of the Process Data Object (PDO)
5.1.1
TxPDO
Fixed places are allocated for the measured values. Dynamic mapping is not possible.
It is possible to operate the T-PDO mode either cyclic, synchronous or asynchronous.
In order to avoid excessive bus usage due to continuous exchanges during not-cyclic
transmission (Event-Time = 0), it is possible to set the so-called
Inhibit time
within
the CAN menu of the serial monitor. It is, however, possible to transmit a PDO cyclically.
In this case, it is necessary to select the Event Time accordingly and also set the Inhibit
Time = 0.
It is possible to permanently deactivate a TxPDO by selecting the asynchronous mode
(255) with Inhibit-Time = 0, Event_time = 0 and storing the parameters. In addition, it
is possible to temporarily deactivate/activate the TxPDO by setting/deleting the high-
est ranking bit within the corresponding PDO COB Identifier.
T-PDO_1 is transmitted together with Identifier 0x180 + Node Address. It contains 7
bytes, which include, amongst others, the status indicated in serial monitor. The trans-
mission sequence is status, X, peak value, digital inputs and barcode. If no code has
been decoded up to now, the value 255 is put out.
The meaning of the status bits is described in Table 7 on page 22.
The synchronous identifier is 0x80. It is possible to read out this parameter under index
[1005,00], but it is not possible to change it.
Value
Variable
Value range
Comment
Status
unsigned 16
0..0xffff
Status bits according to
X1
signed 16
-32768…..+32767
Track deviation within the range of max. -250 [mm] to
+250 [mm]
PEAK
unsigned 16
0....65535
Peak value of the covariance function
Dig. In
unsigned 8
0..0x0f
Status of the 4 digital inputs
Code
unsigned 8
0....99
Barcode
Table 8
Variables of T-PDO_1