User`s guide

50 DC 900-1343D
DDCMP Programmer’s Guide
pOptArgs.iProtModifier field set to 7. The Final Acknowledge of Data Transmitted tells
the client writing DDCMP messages to the serial line that the remote computer has
acknowledged one or more line data messages sent to the ICP serial line. Note that all
line data messages sent to an ICP line are processed in the order sent. The final acknowl-
edge count field is the high-order byte of the
pOptArgs.usProtSequence field and is set
to the number of line data messages being acknowledged. This message is generated by
the ICP.
2.6.1.3 Final Acknowledge of Start Link [9]
The Final Acknowledge of Start Link is indicated by the DLI_PROT_RECV_DATA dlRead
response code with the pOptArgs.iProtModifier field set to 9. The Final Acknowledge
of Start Link informs the client that a successful DDCMP start sequence has been
exchanged with the remote computer. This message is always in response to a previous
Start Link command (Section 2.5.1.3 on page 42). This message type is generated by the
ICP.
2.6.1.4 Final Acknowledge of Stop Link [11]
The Final Acknowledge of Stop Link is indicated by the DLI_PROT_RECV_DATA dlRead
response code with the pOptArgs.iProtModifier field set to 11. The Final Acknowledge
of Stop Link informs the client that the ICP has processed the client stop protocol
request. This message type is generated by the ICP.
2.6.2 Circuit Exceptions
Circuit exceptions are received with the DLI_PROT_RECV_DATA dlRead response code.
The buffer pointed to by the
pBuf parameter contains 16 empty bytes followed by the
received data. The
dlRead iBufLen parameter equals the size of the data (in bytes) + 16.
The
dlRead function normally returns a non-zero pOptArgs.iICPStatus field if there is
an error associated with the message (see Appendix A). However, for circuit exceptions,
the
pOptArgs.iICPStatus field will be zero, and the pOptArgs.iProtModifier field