For Message Frames Without As 512 Protocol And Without Identification - Siemens SINUMERIK 840 Planning Manual

06.91 3 Interface Modules
3.5.2 Addressing lists of the serial interface module
3.5.2.4 For message frames without AS 512 protocol and without
identification
Processing in input direction
The procedure driver of a serial interface recognizes the request to send of the node
connected and handles the operations necessary for data transmission. If a message has been
received without any error, the procedure driver transfers the message frame data (only useful
data since neither protocol nor message frame header are available) to the device
management.
The device management evaluates the entries by means of the interface and addressing list
and transfers the message frame to the SINUMERIK driver.
The SINUMERIK driver checks the message frame data length and interface status and enters
the relevant message frame data, together with the associated address data received from the
COM area at an earlier time and stored in an internal list, in the dual port RAM. There the
COM area calls this data and passes it on.
Processing in output direction
A message frame to be transmitted is stored by the COM area in the dual-port RAM where it is
called by the SINUMERIK driver.
The SINUMERIK driver checks the message frame data length and the status of the interface
and transmits the message frame to the device management. The device management
evaluates the entries in the interface and addressing list that are associated with the message
frame and passes the message frame on to the procedure driver.
The procedure driver informs the node connected of the request to send and handles the
operations necessary for data transmission.
3–49
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SINUMERIK 840/880 (PJ)