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DNT90 Integration Guide - 08/09/12
9.0 Troubleshooting
DNT90E not responding
- make sure /RESET is not asserted (logic low). Make sure the host serial port
settings match the DNT90E serial port settings.
Can not enter protocol mode
- make sure the host data rate is correct. The DNT90E defaults to 9.6 kbps.
If using the
EnterProtocolMode
command, send the complete protocol format for this command.
A remote never detects carrier (DCD)
- check that the base is running, and that the remote’s Sys-
temNwkID is the same as the base, and that the
ParentNwkID
parameter is the same as the base, or is
set to 0xFF. Also make sure that the security keys are the same.
Carrier is detected, but no data appears to be received
- if /HOST_RTS is enabled, make sure it is as-
serted (logic low) to enable character flow from the DNT90E.
Range is extremely limited
- this is usually a sign of a poor antenna connection or the wrong antenna.
Check that the antenna is firmly connected. If possible, remove any obstructions near the antenna.
9.1 Diagnostic Port Commands
The diagnostic port shares its RX and TX signal lines with the Activity and DCD indications, respectively.
Consequently, the debug port feature must be enabled before being used (Bank 0xFF). The change must
be saved and the module then needs to be reset for this to take effect. The diagnostic port is defaulted to
38.4 kbps, 8N1.
The diagnostic port supports the following user commands:
rbr <bank> <reg> <span>
- read a parameter register’s value from the module.
rbw <bank> <reg> <span> <value> [<value> <value>]
- write a parameter register’s value
with a span of up to 3 bytes
stat <option>
- option = 0 is off, option = 1 displays DataTx/AckRx for a hop
sequence in time order, and option = 2 displays any packet RX or packet error for a hop
sequence in frequency order.
base <0 or 1>
- For a router, this determines whether the stat option displays data
associated with its operation as a base (1) or as a remote (0).