COObjRdValue

Description

This function reads the value of the given object directory entry.

Prototype

CPU_INT16S COObjRdValue(CO_OBJ *obj , void *value, CPU_INT08U width, CPU_INT08U nodeid);

Parameter	Description
`obj`	pointer to the CANopen directory entry
`value`	pointer to the result memory
width	width of read value (must be 1, 2 or 4 and reflecting the width of the referenced variable with given parameter pointer: value)
nodeid	device nodeid (only used in case of node-id dependent value)

Returned Value

= CO_ERR.NONE Successful operation

!= CO_ERR.NONE An error is detected (see section "Error Identification")

Additional Information

The access with this function to an object entry will be done with casting of the object entry values to the requested value width.

Example

The following example gets the value of the hypothetical application specific object entry "[1234:56]" within the object directory of the CANopen node AppNode.

    CPU_INT32U  value;
    CO_OBJ     *entry;
    :
    entry = CODirFind     (&(AppNode.Dir), CO_DEV(0x1234,0x56));
    err   = COObjRdValue  (entry, &value, 4, 0);
    :

Note: The example shows a read access with the knowledge, that the addressed object entry is independent from the CANopen node-ID. To be independent from this knowledge, the API function CONmtGetNodeId() may be used to get the current node ID.