User`s guide

5: BSC 2780/3780 DLI Functions
DC 900-1340I 127
response. The BSC 2780/3780 forwards the response to the client with the dlRead
pOptArgs.usProtCommand
field also set to DLI_PROT_SEND_SIGNON. The initiating client
then verifies the other station’s ID and confirms to the BSC 2780/3780 software with
another Signon command (with the
iBufLen parameter set to zero) or a Send EOT com-
mand with the
pOptArgs.usProtCommand field set to DLI_PROT_SEND_EOT. The client
rejects an invalid response ID with a Send Disconnect command with the
pOptArgs.usProtCommand field set to DLI_PROT_SEND_DISC.
After receiving a final confirmation Signon command from the client (valid remote
ID), the BSC 2780/3780 software waits up to two seconds before sending EOT on the
line. The client must send data within this time period to prevent EOT being sent on the
line.
In summary, the following three commands can be used in a signon sequence. Refer to
the diagrams in Section B.1.3 on page 212, which illustrate that each
dlWrite Signon
command results in a
dlRead Signon response (the dlRead pOptArgs.usProtCommand field
is set to
DLI_PROT_SEND_SIGNON by the DLI).
The Signon command is used to:
• initiate a signon bid
• receive a signon bid
• send a signon response
• receive a signon response
• complete a signon procedure
The Send EOT command is used to:
• complete a signon procedure
• reject a signon bid