SAP Note 21368 - SAPcomm, TOPCALL, scmasyn: "No answer received"

Symptom:

No link between SAPcomm and TOPCALL:
The SAPcomm utility program "scmasyn" gives the error message "No answer received".

Cause and prerequisites

With the program "scmasyn", you can send commands via the V.24 port to the TOPCALL and receive and display its answers.
The error message "No answer received" says that "scmasyn" received no response from TOPCALL. This can have many causes, check the the following points:

Solution
a) Is the TOPCALL box installed and in operation ?
If no: Contact your responsible TOPCALL technician.

b) Is the TOPCALL box configured correctly ? The speed of transfer
must correspond to the value set in the SAPcomm configuration file
(PROGRAM TOP, parameter BAUD, default value: 9600), the remaining
transmission parameters must be: even parity, 8 data bits, 2 stop
bits, software handshake (XON/XOFF).
If no: contact your responsible TOPCALL technician.

c) Is the TOPCALL box correctly connected to the V.24 port of the
SAPcomm computer ? Pay attention to the pinouts of the cable: You
need "Transmit", "Receive" and "Ground" connections. "Transmit" and
"Receive" must in this case be swapped between TOPCALL and the
SAPcomm computer !
If no: Contact your responsible TOPCALL technician.

d) Is the TOPCALL box connected to the correct V.24 port ? The port
must be physically attached to the computer which is running
SAPcomm.
It must match the specification in the SAPcomm configuration file
(PROGRAM TOP, parameter PORT, default value: /dev/tty00).
If no: Contact your system administrator.

e) Is the V.24 port being used by another process ? Under UNIX, the
ports are usually assigned "getty" processes which continuously read
the entries from this port (test option with the UNIX command ps -ef
| grep portname.
If yes: Contact your system administrator to get this port
released.

f) Was a TOPCALL command entered during the call of "scmasyn", which
causes a response from TOPCALL (for example: "scmasyn ..i") ? There
are TOPCALL commands which do not give a response (for example
deletion commands such as "scmasyn ..L,K=B:0123456").

g) Is TOPCALL waiting for a confirmation ? After sending a call
command to TOPCALL (..ABRUFEN or ..2QUERY) and receiving a message
from TOPCALL (for example inbound message or daily journal), this
must be confirmed for TOPCALL with a command ..EOT.
TOPCALL does not respond to any other commands until this is done !
For security, "scmasyn ..EOT,ABBR=1" can be entered at any time.

h) Is TOPCALL in text input mode ? Using the TOPCALL command ..T,
TOPCALL changes to text input mode in which all the following
commands are interpreted as text. This mode must be exited at the
end of the text with ..END.
For security, "scmasyn ..END" can be entered at any time.