Siemens SIDOOR ATD401W System Manual page 132

Controllers
4.5 Relay and fieldbus interfaces
Configuration
For efficient communication between DP master (higher-level controller (PLC)) and DP
slave, the DP master has to know how many bytes it sends to the DP slave, and how many
bytes it receives from the DP slave. The values for the outputs and inputs are specified in the
configuration.
The configuration of a DP slave is specified in the GSD file. Before the DP slave can
exchange user data with a DP master, the valid configuration must be transferred from the
DP master to the DP slave and confirmed.
Each DP slave has slots . Each slot can be a module. The SIDOOR ATD420W controller is
designed as a modular DP slave and has exactly one slot. The standard module is available
for this slot.
The configuration for the standard module consists of 22-byte inputs and outputs, and a
manufacturer-specific byte.
The 22-byte inputs and outputs form the process image which, as standard, consists of 7
words for the process data (PZD) and 4 words for the parameter identifier value (PKW). The
reserved manufacturer-specific byte is currently used only as a placeholder.
The configuration described gives the following code for the standard module:
0x15 0x00
Diagnostics
Extensive diagnostic possibilities are supported in the PROFIBUS DP. A DP master can
query the current diagnostics from the DP slave at any time. Diagnostic telegrams can write
additional device-specific diagnostics in the GSD file next to the standard diagnostics.
The DP slave can report in the data telegram at any time that current diagnostics are
queued. To do this it labels its data telegram (High Priority) in the cyclic data communication.
In normal cyclic data communication, the DP slave always answers with a (Low Priority) data
telegram. If an event requires a diagnostic query, the DP slave answers in the next cycle
with high priority. The DP master queries the diagnostics, and continues with the cyclic data
communication.
The diagnostic telegram is divided into several parts. The first 6 bytes and their meanings
are bindingly specified in the standard. The obligatory 6 bytes are followed by optionally one
or several diagnostic blocks.
Three additional device-related diagnostic bytes are defined for the PROFIBUS module. The
first device-related diagnostic byte defines the header, and the next two define the number of
diagnostic bytes.
132
ATD4xxW Door Controller for Industrial Applications
System Manual, 01/2017, A5E38080677-AB
0xC1 0x15