User`s guide

DC 900-1339H 105
Appendix
A
Line Control Procedures
This appendix defines line control procedures for the FMP package.
A.1 DSR Up/Down Reporting
If the data set ready (DSR) signal is lost while a link is active, FMP suspends line oper-
ations for that link and notifies the client with the
DLI_PROT_RESP_ERROR error report
containing the
DLI_ICP_ERR_DSR_DOWN error code. At that time, all ICP message buffers
that are queued for transmission are discarded. The client receives the
DLI_PROT_RESP_LOCAL_ACK data acknowledge with the DLI_ICP_ERR_DSR_DOWN error
code for each discarded message buffer (if the
localAck DLI configuration parameter is
set to “no”).
When the DSR signal returns, FMP sends the client the
DLI_PROT_RESP_ERROR error
report containing the
DLI_ICP_ERR_DSR_UP information code, and normal line opera-
tion resumes.
DSR up/down reporting is disabled when the modem control option is set to HDX-2 or
FDX-2 (Section 4.11 on page 80).
A.2 Freeway/Line Interface
Freeway communicates to remote devices through serial connectors. The ports can be
connected to standard modem cables.