Device Description HG G-71910-C | English, Revision 03 | Date: 17.09.2019
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Components and Operation – Chapter 5
The programming procedure is started by sending 0000.0001
16
in the command
byte of CAN message object 4. Put the code to be programmed into the 4 parameter
bytes.
The one-time programming process lasts 100 to a maximum of 200 ms. Afterwards
the new code can be read out immediately in the corresponding message object.
In case the programming process wasn‘t successful repeat the programming proce
-
dure. A new programming can only be initiated if the command byte has been
switched from 0000.0001
16
to 0000.0000
16
in between.
5.2.2.4 CANopen®
The transponder antenna HG G-71910-C has a CAN interface with the so-called Ba
-
sic CAN protocol. Starting with software version 1.43 the antenna software has been
upgraded to include CANopen® functionality (DS 401). This was achieved by mak
-
ing use of a Micro CANopen library from the company Firma Embedded Systems
Academy, that was specifically modified to work with the processor in use in the an
-
tenna.
The measured values of the system (transponder code, status, etc.) are transmitted
via so-called TPDOs. The parametrization of all relevant parameters (including Node
ID and CAN transmission rate) is realized over the SDO or the serial monitor. The
CAN identifiers derive from the node address (1..127).
5.2.2.4.1 Defaults
The CAN baud rate defaults to 125Kbaud, the Node-ID to 1. Those defaults can ei
-
ther be altered with the help of a terminal program (e.g. Hyperterm on a PC) or via
the SDOs of the CANopen® protocol.
5.2.2.4.2 Description of the Process Data Objects (PDO)
The PDO operational mode can be set to cyclical, synchronous or asynchronous
mode. In order to avoid a bus load being too high due to constant changes during
asynchronous mode with non-cyclical transmission (Event time = 0), the so-called
Inhibit time can be set in the CAN menu of the serial monitor. A PDO can also be
transmitted cyclically, therefore the event time has to be chosen correspondingly
and 0 has to be chosen for inhibit time.
A TPDO can be activated permanently by choosing in the synchronous mode (255)
inhibit time = 0, event_time = 0 and saving of the parameters. Additionally it can be
(de)activated temporary by setting/deleting the highest bit in the corresponding
PDO-COB identifier, e.g. [1800,01]. The measured values are assigned to fixed plac
-
es in the PDO, a dynamic mapping is not possible.
5.2.2.4.3 PDO_1
PDO_1 is sent with Identifier Node address. The PDO contains 6 bytes
consisting of a 32 bit transponder code and a 16 bit status, which corresponds to the
status shown on the serial monitor. The meaning of the data bits is shown in the fol
-
lowing table:
Table 13
Coding of the commands CAN message object 4
Command
Description
Parameter
0000.0000
16
Reset Program Transponder
command
0000.0001
16
Program Transponder
Transponder Code in the area
0x0000.0000
16
to
0x000F.FFFF
16
