Motorola 326X V.34 User Manual page 117

326X Series Modem Troubleshooting Guide (Continued)
Problem Diagnosis/Test
CALL TERMINA-
TION
Modem takes too long to Check to see if remote modem
disconnect supports PSTN cleardown.
Modem doesn't discon- Check modem's DTR option for
nect when DTR drops, correct setting.
or
Modem doesn't discon-
nect when communica-
tions software package
does
Communications soft- Check the delay between issuing
ware package won't sig- the escape sequence (+++) and
nal the modem to return the ATH command.
to command state when
escape sequence (+++)
is issued
Check whether the modem is set
for AT ACU.
FILE TRANSFER
Can't transfer all of a Check the modem's flow control
file or a file aborts in settings.
the middle of transfer
Check whether your
communications package
supports speed conversion.
It takes longer than Confirm which file transfer
expected to transfer a protocol you are using.
file
If operating the 326X-SDC modem in SDC mode, and you experience this type of problem...
BER tests do not work BER tests do not work in SDC
mode because data is not framed.
Modem won't pass data Ensure your DTE protocol is
HDLC/SDLC-like data.
Check for data format mismatch
between modem and DTE
(AT
Check clocking requirements.
*
DF).
Possible Solution
If remote modem doesn't support PSTN cleardown, try to
change the setting of DCD Loss Disconnect (AT
to a smaller number.
• Set DTR to an option other than High.
• Set DTR=Discon (AT&D2).
Ensure the escape sequence (+++) complies with the
modem's guard time requirements (refer to Line feed
character:S-Register 4 for details).
Set ACU Select=AT (ACU OPT's menu).
Ensure that the DTE's flow control is the same as the
modem's setting (for example XON-XOFF, RTS/CTS).
If your communications software supports speed conver-
sion, set modem's Speed Conver=On (AT
Use different protocol, for example, YMODEM,
Y-GMODEM.
If your protocol is not HDLC/SDLC-like, use direct
mode.
Set data format option to match the DTE [NRZ
* *
(AT DF0) or NRZI (AT DF1)].
Set modem for internal or external clock as required by
your application.
*
CD)
* SC1).
Troubleshooting Guide 6-7