Lenze DDS System bus CAN for PLC Uživatelský manuál stáhnout pdf (Strana 153)

System bus (CAN) for Lenze PLC devices

LenzeCanDrv.lib function library

10.7 L_CanPdoTransmit − transmitting a CAN object

10−11

PLC−Systembus EN 2.0

Forced transmission

Some cases may require an entry of a transmit request in the transmit request memory without

considering a data change (event−controlled) or a cycle time (time−controlled).

For this purpose, the L_CanPdoTransmit FB supports the action SendData in the "Forced

transmission" transmit mode (byTransmitMode = 3).

Example

Declaration of the function block in ST:

SendWithID678: L_CanPdoTransmit; (* send data with identifier 678 *)

Calling the function block in ST:

SendWithID678 (wDrvNr:=10,

byLen:=8,

dwCobID:=678,

pIOAdress:=ADR(abySendData),

tRepeatTime:=T#5ms,

byTransmitMode:=3);

Action "Forced transmission" in ST:

SendWithID678.SendData; (* force send procedure *)

Note!

The use of an address which is stored in the memory area of the operating system is not permitted

for the L_CanPdoTransmit and L_CanPdoReceiveFBs!

Problem:

The addresses of the system variables (inputs/outputs of system

blocks) are also placed in the memory area of the operating system, in

the following illustration the system variable AIN1_nIn_a:

Remedy:

Instead of the address of the system variable, use the address of a

temporary variable, which the value of the corresponding system

variable is copied into:

ADR

AIN1_nIn_a

L_CanPdoTransmit

wDrvNr

byLen

dwCobId

pIOAdress

tRepeatTime

byTransmitMode

nState

wNrOfCallsToSend

750

t#10ms

nAnalogInput