6100 ADCCP Programming Manual

(6) START OPERATION
Requests and Responses
6–16 069225 Tandem Computers Incorporated
(6) START
OPERATION
The START OPERATION request and response are used to make a modem connection
to leased lines. For switched lines, see the (68) MODEM CONTROL request and
response.
Request for ADCCP The START OPERATION request causes the ADCCP protocol module to initialize its
driver and to make the modem connection if the line is leased. (For a switched line,
you must use the (68)MODEM CONTROL request and response to make the
connection.)
The request finishes immediately if the line is switched. If the line is leased, ADCCP
asserts the DTR signal and waits for DSR. When DSR appears, the request finishes.
The request buffer format for ADCCP is:
Function := 6
Modifier := 0
Request ID := A unique value from 1 through 32767,
determined by the application.
Text Out := 0
Text In := 0
Text None
Response for ADCCP The START OPERATION response is the expected answer to the START OPERATION
request. It indicates that ADCCP has called the driver and that DSR is present if the
line is leased.
For a list of the status codes and their definitions, see “Status Code Definitions” at the
end of this section.
The response buffer format for ADCCP is:
Response := 6
Status := 0 if the request succeeded, otherwise a
code indicating the error that occurred
Request ID := The same as in the request
Text Out := 0
Text In := 0
Text None
Request for X.21 The START OPERATION request tells ADCCP/X21 to initialize its driver.
If the line is switched, ADCCP/X21 signals “DTE not ready” and completes your
application’s request.
If the line is leased, ADCCP/X21 signals “DTE ready.” When the link enters the data
transfer state, ADCCP/X21 completes your application’s request.