ProSoft Technology PTQ-PDPMV1 - Manual (Page 91)

PTQ-PDPMV1 ♦ Quantum Platform Configuring the Processor with Unity Pro
PROFIBUS DP Master Network Interface Module for Quantum User Manual
ProSoft Technology, Inc. Page 91 of 306
August 12, 2014
3.5 Mailbox Overview
This section provides a brief description on how to use each mailbox function
block. Refer to Mailbox Messaging (page 151) for detailed information about
each mailbox parameter.
3.5.1 Acyclic Read Mailbox
Function Block: ACYCREAD
Trigger Byte: Acyclicread
Description: The ACYCREAD mailbox is used to perform an Acyclic Read
request to a PROFIBUS slave device. The input pins SlaveAddress (PROFIBUS
slave address), SlotNumber (slot number), IndexIn (index number), and LengthIn
(length - number of bytes associated to acyclic read operation) must be
configured before triggering the mailbox request. The acyclic read response data
is copied to the ReadData output pin. The status information is available in the
output pins (ErrorCode, ErrorDecode, ExtendedFaultInfo, and FaultInformation).
The following illustration shows a sample instance of the Acyclic Read mailbox
function block: