Technical data

12.3 FDL_READ_VALUE

This service allows the FMA user to read out the current bus parameters of

the local station.

12.3.1 FDL_READ_VALUE_Request

For the structure of the FDL_READ_VALUE request you must enter the

following parameters in the header:

com_class 0. byte: format KH, service request to layer 2

here:

FDL request =00

user_id 1st byte: freely assignable ID, which is returned

unchanged with a confirmation

(optional)

service_code 2nd byte: format KH, type of service requested:

FDL_READ_VALUE=0B

link_status /

service_class/

SAP number/

rem_add_station/

rem_add_segment

3rd-7th byte: irrelevant

The arrangement of the data in a DB from which they can then be read by

the HDB SEND is explained in more detail in Section 12.9.1.

B8976060/02 Service and Diagnostics using FMA Functions

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