Lenze Function library CANopenSdoDrv - Manual (Page 16)

Function library "CANopenSdoDrv"
Function blocks
BlockRead - read CAN index per segmented data transfer
16
L
DMS 1.0 EN - 07/2011 - TD05
4.3 BlockRead - read CAN index per segmented data transfer
This FB serves to read parameters (CAN indexes) of other devices via system bus (CAN). The
block uses the segmented SDO upload.
 nAddress serves to select the corresponding node where the SDO access is to take place.
A the same time, the parameter channel to be used (SDO1 or SDO2) is selected at the
node via nAddress.
Call possible in: ; Cyclic task
Interrupt task
; Time-controlled task (INTERVAL)
Event-controlled task (EVENT)

Note!
• The FB must be called cyclically in order that the response to the write request
("read response") is detected. Typically, the response arrives only some
program cycles later.
• Make sure that several nodes do not execute an SDO access a node at the
same time via the same parameter channel, since this "collision" would cause
the system bus (CAN) to change to the "bus off" status.
• Do not start several SDO accesses to the same node at the same time. This
causes an incorrect evaluation of the node response.
• Do not use the FBs from the "CANopenSdoDrv.lib" library and the FBs
L_ParWrite and L_ParRead from the "LenzeDrive.lib" library at the same time.
BlockRead
⎯ bExecute bDone ⎯
⎯ nAddress bBusy ⎯
⎯ nIndex nIndexSize ⎯
⎯ nSubIndex bError ⎯
⎯ tRxTimeout dnErrorNo ⎯
⎯ nBufferSize
⎯ pData