Description
The PROFIBUS DP Slave Stack has implemented the required state machines to build a PROFIBUS DP Slave device. In order to fullfill the certification requirements, a correctly behaving application is required in addition.
The stack on its own just provides services that need to be handled correctly by an application for certification and correct behaviour in the field, e. g. evaluating user parameters from master.
Configuration
The stack offers a mailbox interface for configuration. A basic configuration has to be set using a Set Configuration packet first. Additional features can be activated by packets desrcibed in the corresponding API manual. During connection establishment to a PROFIBUS DP Master it is possible to pass parameter and configuration data to the application. Depending on the parameter and/or configuration data the application can reject the incoming connection.
Cyclic data
The stack offers an interface to access the cyclic data.
The cyclic data is either accessed using tripple buffers in case the application is running directly on netX chip or cyclic data is available in the dual-port memory (DPM) which can be accessed by a host application.
Acyclic services
Acyclic services requested by a PROFIBUS DP Master Initiate/Read/Write/Data transport/Abort are indicated to a registered application via the mailbox interface. If no application is registered at the stack all acyclic requests for none-standardized datasets will be responded with an error by the stack automatically.
The stack offers automatic handling of I&M functionality. I&M 0 on slot 0 is handeld internally, other I&Ms are indicated to a registered application via the mailbox interface.
Alarms and diagnosis
The stack offers a mailbox interface for the application to generate diagnosis and add alarm entries to the stack.