Black Box PC001 User Manual page 80

8. After the operator has finished working, he should signoff the application. The system will
UNBIND all the LUs from the host system so that the work station and application are no
longer communicating with each other. This leaves the work station available for an operator
to logon to another application. SSCP may send an enter request logon message which puts
the work station back to step 4 so as to start things over again.
Batch Terms:
Function Management Header 1 (FMH-1) is used to select a destination within an LU. When sent by the
A/S-4 it indicates to the host which device (card reader or console) is sending data to the host, used in
the same way when host sends FMH-1 to the A/S-4.
Function Management Header 2 (FMH-2) specifies the data management activities to be performed at
the destination selected with the FMH-1. Typical data management activities are adding and replacing
records, numbers of copies to print and date data created.
APPENDIX B: General 3770 SNA Communication Operations
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