Murata Electronics North America 5811M Manual Do Utilizador
© 2003 Cirronet
Incorporated
28
M-5811-0008 Rev -
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.
Receiving terminal drops characters periodically.
Set the number of retries to a high number and send a few characters. Check that the
transmitted data can get through under these conditions. Sometimes this symptom is caused
by an application that is explicitly dependent on the timing of the received data stream. The
nature of the packetized RF channel imposes a degree of unpredictability in the end-to-end
transmission delay.
Cannot communicate with the OEM module.
Make sure DTR and RTS are asserted. DSR should be on to indicate the radio is ready.
OEM Module is in an unknown state.
Use the
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.
Receiving terminal drops characters periodically.
Set the number of retries to a high number and send a few characters. Check that the
transmitted data can get through under these conditions. Sometimes this symptom is caused
by an application that is explicitly dependent on the timing of the received data stream. The
nature of the packetized RF channel imposes a degree of unpredictability in the end-to-end
transmission delay.
Cannot communicate with the OEM module.
Make sure DTR and RTS are asserted. DSR should be on to indicate the radio is ready.
OEM Module is in an unknown state.
Use the
m0
command to restore the factory defaults. Note that the serial baud rate must be
known for the module to receive this command.