User`s guide

42 DC 900-1343D
DDCMP Programmer’s Guide
Table 3–1 on page 56 lists the available link configuration options and values for the
DDCMP protocol. The link status report (Section 2.5.2.3 on page 46) gives the current
settings for a link’s configuration options.
2.5.1.2 Clear Link Statistics Command
Use the dlWrite function with the pOptArgs.usProtCommand field set to
DLI_PROT_CLR_STATISTICS to clear the link statistics report. The link statistics are
cleared as soon as this command is received. The statistics are automatically cleared
when a Start Link command (Section 2.5.1.3) is issued.
A
dlRead link statistics report response (the pOptArgs.usProtCommand field is set to
DLI_PROT_CLR_STATISTICS by the DLI) is automatically returned to the client, contain-
ing the link statistics prior to clearing. The format is shown in Section 2.5.2.2 on
page 45.
2.5.1.3 Start Link Command
Use the dlWrite function with the pOptArgs.usProtCommand field set to
DLI_PROT_SEND_BIND and the pOptArgs.usICPCommand field set to DLI_ICP_CMD_BIND to
start a link. After receiving this command, the DDCMP software turns on the DTR
modem control signal and prepares the link to transmit and receive data according to
the current link configuration settings. After a link starts, data transmission can begin
on the line.
The first
dlRead response (the pOptArgs.usProtCommand field is set to
DLI_PROT_SEND_BIND by the DLI) is sent to the client to acknowledge ICP receipt of the
Start Link command. However, the link is not considered started until the client
receives the
dlRead final acknowledgment response (the pOptArgs.usProtCommand field
is set to
DLI_PROT_RECV_DATA by and the pOptArgs.iProtModifier field is set to “Final
Acknowledge of Start Link” as described in Section 2.6.1.3 on page 50).