User`s guide

5: BSC 2780/3780 DLI Functions
DC 900-1340I 129
When issuing a Poll Line command, wait until the data acknowledge response is
returned from the command before issuing another Poll Line command. If the data
acknowledge response from the Poll Line command is never received (usually because
it was issued to a line with no clock signals), use the Flush Queue command to cancel
the Poll Line and return the data acknowledge response.
If the poll cannot be attempted, the Poll Line with No Data command can return one of
the following error codes in the
dlRead pOptArgs.iICPStatus field (see Appendix D for
error handling):
DLI_ICP_ERR_BAD_MODE
The function request is not available for the requested
access mode.
Table 5–5: BSC 2780/3780 Error Responses on Poll Failure
Local Acknowledge
pOptArgs.iICPStatus
Field Error Code
Meaning Reason for Error
DLI_ICP_ERR_XMIT_ABORTED
EOT abort The remote station sent EOT instead of ACK0 in
response to the ENQ poll.
DLI_ICP_ERR_RETRY_EXCEEDED
Retry limit
exceeded
The remote station did not respond to the bid
within the number of retries specified by the Retry
Limit option.
DLI_ICP_ERR_DSR_DOWN
DSR or DCD
down
The poll was not issued because the Data Set Ready
(DSR) or Data Carrier Detect (DCD) modem sig-
nal was low. This error occurs only when the
Modem Control option is set to HDX-1 or FDX-1
(for DSR) or HDX-3 or FDX-3 (for DCD).
DLI_ICP_ERR_NO_CLIENT
Line busy The poll was not issued for one of the following
reasons: 1) the link is waiting for a response from
the remote station, 2) the link is waiting for a Safe
Store Acknowledge command from the client, or
3) the poll was requested using Control mode, and
a data message is currently being transmitted or
received.
DLI_ICP_ERR_USER_ABORT
User abort The poll was canceled because a Flush Queue com-
mand was issued by the client.