ProSoft Technology PTQ-PDPMV1 - Manual (Page 87)

PTQ-PDPMV1 ♦ Quantum Platform Configuring the Processor with Unity Pro
PROFIBUS DP Master Network Interface Module for Quantum User Manual
ProSoft Technology, Inc. Page 87 of 306
August 12, 2014
3.4.3 Trigger Bytes
Mailbox requests are initiated by "triggers" (bytes) that are defined as
input/output pins. A mailbox request is initiated after the application moves a
value of 1 to the appropriate trigger byte.
Only one mailbox function may be active at any given time. Therefore, in order
for a mailbox request to be carried out, the value of all mailbox triggers in your
application must be equal to 0 at the time the request is made. If you are using
more than one mailbox function block, add program code to guarantee that this
condition is satisfied.
The processor will only allow a new mailbox request to be sent out after it has
received confirmation that the previous mailbox request was acknowledged by
the module. The processor determines this condition by checking the status of all
trigger bytes (0=OK). This procedure also prevents more than one mailbox
request from being sent out during a single PLC scan.
The following table shows the trigger bytes used for each mailbox function block:
Function Block Name Description Trigger
ACYCREAD Acyclic Read Mailbox Acyclicread
ACYCLWRITE Acyclic Write Mailbox Acyclicwrite
GETALARMS Alarm Mailbox -
GETCFG Get Configuration Mailbox GetConfig
GETDIAGNOSTICS Get Diagnostics Mailbox GetDiagnostics
GETLIVE Get Live List Mailbox GetList
SETADDRESS Set Slave Address Mailbox SetAddress
SETOPERMODE Set Operating Mode Mailbox SetOperate, SetStop, SetClear
SETSLMODE Set Slave Mode Mailbox SetSlaveMode
STARTSTOPSLAVE Set Start and Stop Slaves Dynamically StartSlaves, StopSlaves
COLDBOOT Remote Coldboot from PLC ColdBoot