Murata Electronics North America 910M Manuale Utente
WIT910
6.3. Troubleshooting
Radio is not responding.
Make sure DTR is asserted to bring the radio out of sleep mode. DSR should be on to
indicate the radio is ready.
Can’t enter modem control mode.
Make sure the host data rate is correct. The WIT910 defaults to 9600 bps asynchronous.
Evaluation units do not have external access to the CFG_SEL signal; you must use the
:wit2410 power-on escape sequence to access modem control mode. The first characters
typed after the radio wakes up should be the escape sequence. Make sure you type the
colon (:) and enter the letters in lower case; the characters following the colon echo to
show you have typed them correctly. If using the “on-the-fly” escape sequence command,
make sure a pause of at least 20ms precedes the escape sequence.
Remote never detects carrier.
Check that the base station is running, and that the remote is programmed to the same
hopping pattern. Also check that the hop duration for base and remote are the same, and
that the remote has a non-zero link margin.
Carrier is detected, but no data appears to be received.
Make sure that RTS is asserted to enable receive character flow. In a point-to-point
application, if a remote is not receiving data, check that the base's default handle is the
same as the remote's. In a multipoint application, check that the remote is not configured
for protocol mode and that the base is using the correct protocol format and destination
handle.
Make sure DTR is asserted to bring the radio out of sleep mode. DSR should be on to
indicate the radio is ready.
Can’t enter modem control mode.
Make sure the host data rate is correct. The WIT910 defaults to 9600 bps asynchronous.
Evaluation units do not have external access to the CFG_SEL signal; you must use the
:wit2410 power-on escape sequence to access modem control mode. The first characters
typed after the radio wakes up should be the escape sequence. Make sure you type the
colon (:) and enter the letters in lower case; the characters following the colon echo to
show you have typed them correctly. If using the “on-the-fly” escape sequence command,
make sure a pause of at least 20ms precedes the escape sequence.
Remote never detects carrier.
Check that the base station is running, and that the remote is programmed to the same
hopping pattern. Also check that the hop duration for base and remote are the same, and
that the remote has a non-zero link margin.
Carrier is detected, but no data appears to be received.
Make sure that RTS is asserted to enable receive character flow. In a point-to-point
application, if a remote is not receiving data, check that the base's default handle is the
same as the remote's. In a multipoint application, check that the remote is not configured
for protocol mode and that the base is using the correct protocol format and destination
handle.
Radio is interfering with other nearby circuits.
It is possible for the RF energy envelope to be rectified by nearby circuits that are not
shielded for RFI, manifesting as a lower frequency noise signal. If possible, place the
antenna at least 1 foot away from the transceiver module, and 3 feet from other circuit
boards and obstructions. Place sensitive circuits in a grounded metal casing to keep out
RFI.
Sign-on banner or modem control mode prompt is unreadable.
If the problem is repeatable, check whether the data rates between host and transceiver
match.
Range is extremely limited.
This is usually a sign of poor antenna coupling. Check that the antenna is firmly
connected. If possible, remove any obstructions in the near field of the antenna (~3'
radius).
Transmitting terminal flashes CTS occasionally.
This indicates that the transmitter is unable to reliably get its data across. This may be
the result of an interfering signal, but most often is caused by overloading of the network.
Adjusting the protocol parameters may increase the network efficiency.
It is possible for the RF energy envelope to be rectified by nearby circuits that are not
shielded for RFI, manifesting as a lower frequency noise signal. If possible, place the
antenna at least 1 foot away from the transceiver module, and 3 feet from other circuit
boards and obstructions. Place sensitive circuits in a grounded metal casing to keep out
RFI.
Sign-on banner or modem control mode prompt is unreadable.
If the problem is repeatable, check whether the data rates between host and transceiver
match.
Range is extremely limited.
This is usually a sign of poor antenna coupling. Check that the antenna is firmly
connected. If possible, remove any obstructions in the near field of the antenna (~3'
radius).
Transmitting terminal flashes CTS occasionally.
This indicates that the transmitter is unable to reliably get its data across. This may be
the result of an interfering signal, but most often is caused by overloading of the network.
Adjusting the protocol parameters may increase the network efficiency.
© 2000- 2004 Cirronet™ Inc
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M-0910-0000 Rev -