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RMPSendMessage

This function block serves to send messages to any module instance. The address of the instance must be known.

The behavior of the variables xExecute, xDone, xBusy, and xError complies with the "Guidelines for Library Design". This document is part of the CODESYS standard installation.

FUNCTION_BLOCK: RMPSendMessage

FUNCTION_BLOCK RMPSendMessage EXTENDS CBM.ETRIG
VAR_IN_OUT
    mdData: ARRAY[0..63] OF BYTE;
END_VAR
VAR_INPUT
    itfrmp: IRMPService;
    xExecute: BOOL;
    udiReceiverID: UDINT;
    uiSenderModuleID: UINT;
    tValidity: TIME := t#1s;
END_VAR
VAR_OUTPUT
    xDone: BOOL;
    xBusy: BOOL;
    xError: BOOL;
    uiErrorID: UINT;
END_VAR

Please note that the job of the function block is finished successfully as soon as the receipt of the message in the RMPService of the opposite side is confirmed. This does not necessarily mean that the message has reached the actual receiver module interface.

In mdData, the data to send will be transferred. udiReceiverID defines the ID of the receiver.rmp defines the local RMPService instance.

. tValidity defines the validation period of the message. The following things are checked:

  • The duration until the message is sent must not exceed tValidity (otherwise an error message will be created).

  • The duration until the message is picked up by the receiver of the opposite side, must not exceed tValidity (otherwise the message will be deleted).

. The following errors may occur and will be returned in uiErrorID:

  • Send buffer is full; it is recommended to send again at a later date.

  • The message will not be deleted from the send buffer. Reasons can be a slow transfer, an interrupted connection or a full receive buffer on the opposite side.

  • The application to which the message is sent is not connected to this application. In this case a transfer of the data is no possible.

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