TPDO Event

The TPDO component provides an interface to the CANopen PDO transmission triggers.

Module Context

classDiagram
  CO_NODE o-- CO_TPDO
  CO_OBJ o-- CO_TPDO : Map
  class CO_TPDO {
    -uint32_t Identifier
    -int16_t EvTmr
    -uint16_t Event
    -int16_t InTmr
    -uint16_t Inhibit
    -uint8_t Flags
    -uint8_t ObjNum
    -uint8_t Size[]
    +COTPdoTrigObj(obj)
    +COTPdoTrigPdo(num)
  }

Structure Data

The class CO_TPDO is defined within co_tpdo.h and is responsible for the CANopen transmit process data objects (TPDO). The following data members are in this class:

Data Member	Type	Description
Event	uint16_t	event time in timer ticks
EvTmr	int16_t	event timer identifier
Flags	uint8_t	transmit status flags
Identifier	uint32_t	CAN message identifier
Inhibit	uint16_t	inhibit timer in timer ticks
InTmr	int16_t	inhibit timer identifier
Map[]	CO_OBJ*	pointer list to mapped object entries
Size[]	uint8_t*	size of mapped values in PDO payload
Node	CO_NODE*	pointer to parent node
ObjNum	uint8_t	number of mapped object entries

Info

The data within this structure must never be manipulated without the corresponding class member functions. This can lead to unpredictable behavior of the node.

Member Functions

The following table describes the API functions of the CANopen transmit PDO module. These functions are implemented within the source file: co_tpdo.c/h

COTPdoTrigObj()

The event will be distributed to all TPDOs, which holds an active mapping entry to this object entry.

Prototype

void COTPdoTrigObj(CO_TPDO *pdo, CO_OBJ *obj);

Arguments

Parameter	Description
pdo	pointer to start of TPDO array
obj	pointer to object entry

Returned Value

• none

Example

The following example triggers the transmission of all TPDOs of the CANopen node AppNode, which contains the hypothetical object directory entry "[1234:56]".

CO_OBJ *entry;
  :
entry = CODirFind(&(AppNode.Dir), CO_DEV(0x1234, 0x56));
COTPdoTrigObj(&(AppNode.TPdo[0]), entry);
  :

COTPdoTrigPdo()

The function call will immediately initiate the TPDO transmission, independent on the TPDO communication type settings in the object dictionary.

Prototype

void COTPdoTrigPdo(CO_TPDO *pdo, uint16_t num);

Arguments

Parameter	Description
pdo	pointer to start of TPDO array
num	number of TPDO (0..511)

Returned Value

• none

Example

The following example triggers the transmission of TPDO #3 of the CANopen node AppNode.

  :
COTPdoTrigPdo(&(AppNode.TPdo[0]), 3);
  :