Temposonics
®
MH Digital
Operating Manual
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19
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10.2 System start
CANopen & CANopen Safety
After configuration of the node parameters, the sensor can be integrated into the network. When switching on, or after reset, the sensor under-
goes hardware initialization. During this procedure, all components are set into a defined initial state. Subsequently, the sensor loads the instru-
ment and communication-specific parameters from an EEPROM and saves them for configuration.
When the initialization has been completed, the sensor transmits a boot-up message to the network master saying that the sensor is now in pre-
operational mode and including its node ID in the network. In this network, the sensor can be configured using the service data objects (SDOs)
(see also: Setting the Operating Parameters).
According to the CANopen standard, the SDO identifiers are formed automatically using the node IDs. The communication via SDOs for configu-
ration of the sensor represents peer-to-peer communication from the network master to the sensor.
The identifiers for the remaining objects are defined according to the CANopen standard as well. However, a change can be realized in the
CANopen network at all times via a DBT master. If the need arises, changed parameters can be saved in EEPROM and are used for configuration
automatically when switching on for the next time.
After completing the settings, the sensor is switched from pre-operational to operational mode using a Start_Remote_Node command. During
this mode, data can be transmitted (via PDOs). There are two possible ways for transmission of the PDOs. Either the sensor sends its data cycli-
cally, or data transmission is triggered by reception of a SYNC object.
To send position messages, please run ,node start’ message first
Data source
COB-ID
Data
Destination
Controller
0x000
01;
00*
; 00; 00; 00; 00; 00; 00
Sensor
* 00
Starts all node ID
Source address
Starts only one node ID
To stop position data’s, send the ,Enter Pre-Operational’ message first.
Data source
COB-ID
Data
Destination
Controller
0x000
80;
00*
; 00; 00; 00; 00; 00; 00
Sensor
* 00
Set all node ID in Pre-Operational mode
Source address
Set only one node ID in Pre-Operational mode
SAE J1939
After connecting the sensor to the network and switching on, the sensor attempts to register with the network master using a source address.
This address claiming is performed automatically by the network. After assignment of a unique network address, the sensor starts sending the
position data. At the same time, the sensor is ready for reception of configuration data.
CANopen